Re: Drunk Paki
Depending on how bad the assault was (you said they "almost" assaulted), I'd call the police if needed - i.e. in a situation where the owner or staff aren't able to do so themselves. Otherwise, rowdy drunk customers are fairly common in the restaurant business esp. those that are open late, and for the most part, the staff knows how to deal with them.
Re: drunk Pakis... seen quite a few - coincidentally, a couple of times in NYC, but you'd find them everywhere. I suppose some would argue that drinking is your prerogative, but if you can't hold your liquor, then you need to realize that on your own.