Face it there are exhibitionists among us. Although I'd not want them to do that, I also think it is wrong to physically attack someone that hasn't posed a physical threat to anyone. Imo, all those videoed are guilty of a crime.
I get the anger of the guy with the bike, but there are so many other ways you could have stop that. Cup a cold water would have been just as affective.
The hitter... there are (apparently) kids present... exposing them to such unprovoked violence is unforgivable. Weird how our society views violence as more acceptable then sex... very backwards.