Depending on where the bathrooms are located, yes they might. You really have to scope out the situation for each bar and figure out when the most likely time for you to be able to get away with it might be. We've usually found that the lull between performances is NOT a good time unless the bar has a backup band or stereo system to keep the people dancing. Watch the bathrooms until you're sure that everyone who went in is out before you go for it. Some other things we've learned:

Choose the male's bathroom and lock the door if you can. If not, then use a stall and lock it. Keep the noise down as much as possible, be quick, and if anyone says anything act like you're sick and he was tending to you. It *does* work most of the time. Oh, and for the whys of choosing the male bathroom-- chicks are most likely to go whining to management if they know a man's in the women's room. Guys are more apt to just hit you with ribald remarks as you're leaving. Also, if you wind up using a stall, gals are more prone to stand in there and gossip (upping your chances for being discovered) while guys will generally piss and get out and not be nosy about who's in the stalls.

And for fuck's sake, do not go into the bathroom hand-in-hand giggling and looking guilty (we saw a couple do that once.) Let him go in, then wait a minute and follow him as casually as if you thought you were walking into the women's room, which is another excuse you can use if you're caught right at the start.

that is a little to risky for me even though hubby and I had sex in a movie theater once