"You" is a nebulous term during any mass action. If provocateurs[1] can unilaterally turn a legitimate protest into a "riot" in a way that materially changes the rules of engagment, i.e. if a single anonymous person among thousands can instantly change a constitutionally protected activity into a crime for everyone present, then having a legally defined distinction that is easily subvertible may not be a great idea.

Nevermind the fact that guilt-by-physical-proximity-to-a-criminal is a legally-dubious concept.

1. Embedded counter-protesters or undercover law enforcement