Except in Maysie's example the asshole is is noisy and easily spotable for the bouncer/bartender etc. The NZ ad it is not so obvious and someone could easily be wrong if they interfered and found out it wasnt what it seemd.
The Maysie example he seemed and is an abusive asshole ruining fun for everyone
The Creeper is not as obvious. otherwise I would agree they should step in, much as I have seen them do in bars/clubs where a guy was grabby, creepy abusive to every woman he saw. Especially if anyone complained.
And if anyone said anything to a oblivious or otherwise busy bouncer/bartender I would expectr them to take action as well, even if its just to inquire if anyone needs help