I sort of feel the same way. I also think that Europeans tend to have more budget to travel to the USA and there seems to be an expectation that the family will host them (for some anyway). It's important to set expectations right from the beginning. I too do only one week, twice per year, 2 people max. I make one big dinner for everyone. It can feel overwhelming since they are on vacation and yet our family continues to travel at whirlwind pace as usual. Also, it is all nice, new and exciting to them since it is likely their first experience with the USA. For us, it is literally year after year that we have Au Pair visitors. That part becomes really tiring to me.
I also find that all of the French who stay with us really don't want to spend money on hotels and go great lengths not to do this... last year our AP was with her parents for a couple of nights out of town and got caught in a snow storm while they were there...it was declared a state of emergency in our town (I texted AP to let her know)...they still drove through the snow storm in a little rental car so they didn't have to spend another night in a hotel.
And I agree with you... I really hate hosting anyone (including my own family) when I am not off from work...our life is crazy enough and it just stresses me to the max.
Also, you hit the nail on the head...I am really over it after hosting AP parents year after year...