Please don't have such a knee-jerk, childish response. Such spirit days are the province of the counselor in our school, not the PTA. Most of the PTA's work may be invisible to you.
I volunteered on the board of an elementary PTA for many years. Pre-Covid, we:
1. fundraised (parents just donated online or write checks)
2. paid teachers for tutoring the kids who need it,
3. had a pantry where we organize food backpacks,
4. organized a STEM fair and science activities throughout the year,
5. organized cultural arts activities where artists presented their craft and led each grade in a similar age-appropriate session (it's a play-writing and acting for the older grade that lasts a month),
6. helped out the teachers when they need it,
7. discussed long-term demographic issues (building around us is crazy, school is overcrowded, must change boundaries and build a new school), car safety around the school (getting worse), shared land use, (dog owners using the playground) etc, with the Principal and the relevant county and business reps, and actively represented the students' interests in those respects at the appropriate meetings all around the county,
8. plus many things I'm forgetting, like book fairs, etc.
We are at a wealthy school where a lot of parents know how to wield influence, so when they end up on the PTA Board, they use those skills to fight for students and teachers. The Principal is savvy and knows how to navigate MCPS rules so that the funds she receives are maximized and teachers can be hired during the hiring window at the beginning of the year, when it appears the incoming classes are too large. However, with the amount of building around us and constant influx of students, it's still very difficult to deal with overcrowding.
What you mention, OP, is such a minuscule part of a school's functioning that you come off as petty when you complain about it, regardless of whether it comes from the PTA or counselor or whoever. There are a lot of things your PTA probably does that your child has benefited from, without your even knowing about it. Please just IGNORE the multitude of activities you do not wish to participate in. My children never did the spirit days, but loved pyjama day, for example. At the high school level, there are so many activities and "days" that it's just impossible to participate in all of them!