Two most common cases that I've seen. Both are cases of learned behavior that the parents did not correct.
1. Parents were rude and dismissive growing up and child imitates them. We become our parents as we get older.
2. Learned behavior from peers, usually peers in school, but often peers in extracurricular activities (like sports, scouts, dance, etc) and the parents did not correct and allowed it to continue until it became habitual.

Anonymous wrote:When we were growing up, I would say yes, behavior was modeled. We did not have the influences of social media. My W does research in this area and one should not underestimate its power.

I think different generations take away different learned behavior. DH’s grandmother was amazing. If she asked for something of course anyone would do it BUT she seldom asked. She was never intrusive and if she judged people she never bothered to express it. Now her big failing was raising a bunch of selfish boomers always jockeying to get more. They seem to interpret hmm..everyone does whatever mother (grandmother to their kids wants) so my kids and nieces / nephews should do whatever I want. They all totally missed that grandma seldom asked, had no problem accepting no if it wasn’t logistical etc and gave more than she took. These boomers are insatiable in how much and how often they want something. They’re competitive too so if they see a sibling is getting something it’s full on attack their own kids to give it to them too. To the boomers not giving me what I want is rude.

The next generation down genx and millennials is really, really sick of the boomers. Older genx just seethes, ignores and tries to avoid while the millennials seem to confront the boomer demands with either a firm no or therapy speak about boundaries which enrages the boomers. I do think that social media has played a role in boomers competitive demands and giving millennials to just say no.

When we were growing up, I would say yes, behavior was modeled. We did not have the influences of social media. My W does research in this area and one should not underestimate its power.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Are they rude to everyone? Or just to you? That will be a big hint.

Only to family members, at times but not all the time. I do see him same way with his wife. Very loving and daring but could just be rude to her when she is unreasonable. Compared to him, my other brothers would never raise their voices or lose their cool even if they get upset.

It may not be rudeness, then. If he is polite and well-mannered with people outside his family, and also with his wife under most circumstances, then there is something about his relationship to his family that is driving his behavior.

As other PPs have pointed out, sometimes people become "rude" because their needs are not met when they are polite. I have discovered I have to be extremely blunt with my mom to get her to listen to me at times, to the point of using sometimes sharp words with her. She has untreated mental health issues and can become manic and anxious and will just ignore everything I'm saying, violate boundaries, work herself up. I have literally shouted at her just to get her to stop during one of these episodes, because I am worried she will do something to harm me or my child. This is not "rude." It's survival.

"People become rude when their needs are not met when they are polite" ... that sure sounds like umbrella justification for all every rude person.

Anonymous wrote:Note how OP hasn’t answered a single question, probably because she realizes she is guilty of some of the behavior described here. How very interesting that she can’t even take accountability anonymously online.

Its amusing when random posters play triple role of judge, jury and executioner.

My parents were constantly sarcastic and dismissive to me when I was growing up. If I said "my stomach hurts" they'd respond with something like "oh does it? wow, sucks for you."

I became a very sarcastic, dismissive adult, then quickly discovered that's sort of a miserable personality, went to therapy, and became someone who rarely uses sarcasm and even then never in a dismissive way, and is a much more direct but also loving person than I was as a teenager and in my early 20s.

But even now, if I'm talking to my parents and they say something that annoys me or that I disagree with, I will still sometimes respond in the brattiest, most sarcastic, teenage way. Anyone else, I'd be able to control it. My parents, and especially my dad? It's so hard. Those patterns are SO engrained in our relationship.

It's something I think about with my own child all the time. She will speak to me the way I speak to her. I am kind, polite, respectful, and understanding with her.

Anonymous wrote:

Anonymous wrote:Are they rude to everyone? Or just to you? That will be a big hint.

Only to family members, at times but not all the time. I do see him same way with his wife. Very loving and daring but could just be rude to her when she is unreasonable. Compared to him, my other brothers would never raise their voices or lose their cool even if they get upset.

It may not be rudeness, then. If he is polite and well-mannered with people outside his family, and also with his wife under most circumstances, then there is something about his relationship to his family that is driving his behavior.

As other PPs have pointed out, sometimes people become "rude" because their needs are not met when they are polite. I have discovered I have to be extremely blunt with my mom to get her to listen to me at times, to the point of using sometimes sharp words with her. She has untreated mental health issues and can become manic and anxious and will just ignore everything I'm saying, violate boundaries, work herself up. I have literally shouted at her just to get her to stop during one of these episodes, because I am worried she will do something to harm me or my child. This is not "rude." It's survival.

Anonymous wrote:Typically the behavior was modeled for them when growing up.

This. x1000. Rudeness is learned behavior (from parents or people around them)

Anonymous wrote:

Anonymous wrote:Is this because they don't want your boomer hoard of stuff?

Lol I was just thinking this.

If you don’t take no thank you or that won’t work for as as a complete and final sentence then you are pushing them toward having to be rude. I know that you expect them to give in to your constant repeated badgering and pout pout face but you are the one being rude. The only path you eventually leave them is to be rude back to you with a firm NO.

This.

Note how OP hasn’t answered a single question, probably because she realizes she is guilty of some of the behavior described here. How very interesting that she can’t even take accountability anonymously online.

I confess to having been pretty rude to my mother many times.

It was always because I couldn't take her poor behavior (much of it alcohol related, some of it related to personality issues), and I'd react. When younger, I didn't realize how bad her behavior was. Once I was an adult, I did, and I would get quite frustrated with it and lash out. Not proud of it, but that is how it was.

Is this because they are trying to get you to stop your diet talk around their kids?

Is it because you don't believe food allergies exist and you keep exposing their children to allergens?

Is it because you don't believe in car seats?

Is it because they don't want your stuff?

Is it because you're MAGA?

Is it because you smoke cigarettes?

Anonymous wrote:Is this because they don't want your boomer hoard of stuff?

Lol I was just thinking this.

If you don’t take no thank you or that won’t work for as as a complete and final sentence then you are pushing them toward having to be rude. I know that you expect them to give in to your constant repeated badgering and pout pout face but you are the one being rude. The only path you eventually leave them is to be rude back to you with a firm NO.

Is this because they don't want your boomer hoard of stuff?

The parents allow it. My kid would only be rude to me ONE TIME, then life as he knows it, would drastically change.