Of course. If I'm going to go to a bar or other establishment with the intention of meeting someone then I'm not going to get upset if someone comes onto me, and I would of course, also, approach someone who interested me and let them come onto me, as well.
I'm a social creature just like most people, I like to think, and very open minded. I'm not opposed to someone coming up to me to get to know me or for that matter, me approaching someone else, a stranger, to get to know them in return. If you're going to go to these places you might as well make the most out of where you are and having fun. As long as that's happening, so much the better and why's to worry.