Yes yes and yes. My home has completely lost gay bars because the number of straight tourists has driven gay people out or made the space unsafe by both numbers or by grossly obnoxious behaviour
There are almost no spaces in the world where LGBT people are not an inherent minority. That's not even a comment on homophobia, that's simple demographics. Even the most generous metrics put LGBT people at about 10% of the population. We are inherently a minority, we will always be, inherently, a minority. Which means 99.9% of everywhere we go all the time we are surrounded by people not like us. All the time (this was an amusing revelation to one of my colleagues lately). So yes, I - and many others - are very protective of the teeny tiny spaces we managed to carve out in this HUGE STRAIGHT WORLD where, for a few blissful moments, we can be us, surrounded by us, knowing everyone around us is... us.
And before anyone cries about it "not being fair". Cis, straight folks - you have the world. The entire freaking world. Every day is straight pride day. Every bar is a straight bar (where we're still evicted on a regular basis). You never have to be careful, being a cis straight person in an LGBT world. You never have to be afraid, being a cis straight person in an LGBT world. You are not the only one of your sexuality or gender identity in a room. You do not have that daily pressure not to be you because you are cis and straight. We need these guarded corners because you have filled the rest of the space with your overwhelming presence but also your overwhelming culture of superiority and hostility - and that's a culture that follows you EVEN IF you are fighting against that. No matter how much of an ally you are, your presence adds to the majority, a majority which, frankly, frightens me.
And, really, you've got the whole world. You object to our tiny corners?