I think you can stave this off by trying to sit for parades/fireworks.
There could be many reasons why someone doesn't want to sit down on pavement. It can be cold or hot, wet, dirty. They could have issues getting up and down (dh has a bad back and get up and down is painful at times also he takes a lot of room to stand back up so he can get run over by crowds after the parade). If you are sitting and the people in front are standing no matter how tall you are you can't see. If someone is standing and you decide to stand behind someone who is standing it's really your fault if you can't see