While I know what you mean, and I had the same thought when I was young and first realised that gay bars is a gold mine, no I couldn't disagree further in principle.
The gays, of all people, shouldn't feel we should be limiting things to "their space" and "our space" as long as everyone is respectful towards each other, there really shouldn't be a defined "gay bar" in the first place, and the idea is becoming extinct, I've known gay people who take issue with the idea itself.
I don't mean going to a gay bar to be a sex pest towards some women who felt they were safe from lurching men, but if you are a respectful person who acknowledges promising signs from women or lack thereof, there is nothing morally wrong with going out to them to have a good night and see what happens.
Basically, the rules change quite a bit, I'd never just start chatting up some girl in a gay bar who probably went to have a fun night with her gay friend, the aggressive tactics we deploy normally shouldn't apply there.