I don’t think they are many, they are a minority, but a dangerous one. One rapist can rape several women. That means that even if they are a minority, they are common enough to be a risk. And the thing is, they won’t call it rape. They would say “pick up”. And while is not openly admitted, there are a significant number of men who use alcohol as a way to “smooth things”. At some point, part of them lose perspective and think that is “normal” to get the woman drunk in order to “get laid”.
It is normal that people have friends with similar views. So if you would never do something like that, chances are that your friends won’t either. But there are groups where all the men would do things like that. Since that kind of men are set on “picking up girls”, chances are that those men would be the first to approach a woman. So while they are a minority, it is a very visible one and can cause serious trust issues for women when going out.
I mean, most women have had men like that approach them at bars. And while that kind of men is talking to you (and ignoring your lack of interest), the other normal men won’t approach because from the outside it looks as if we are “already accompanied”. And barring from being really rude, those men won’t let you go or finish the conversation, they would keep insisting because “when a woman say no, she mean yes/perhaps”. You’ll be surprised the kind of shit we see at bars. I’ve even got bitten. Literal. And no, I wasn’t making out with the guy, not interested in the slightest. So yes, that kind of thing is common enough.
And lets not pretend that men buy drinks for no reason. We do know that there’s a significant number that expect to get laid in exchange for those drinks.