Why so little faith in the police? Do you really think they're incapable of judging when someone's had "too much"? If they can do it for street types, why not in bars?
Obviously I'm not cheering an outright ban on drinking in bars; I just want to see things kept in moderation. Everything I said about rowdy drunks on the streets applies to bars, too. People turn into the biggest scumbags at that level of drunkedness. Why on earth shouldn't we try to do something about it? Indeed, in Australia, at least, much is being done to curb your typical Aussie's penchant for getting wasted, but it's mostly proprietors themselves following liquor authority guidelines. But getting some cops in there wouldn't be a bad idea either.
People deal with this by avoiding bars known for their rough crowds, but not everybody in those bars is the rough type. They are people, usually poorer, and deserve some protection, too. I really don't see why society should countenance obscene drunkards. (Sure, bouncers toss them out, but they need to feel more of a sting if they're to change their behaviour.)