If you have gay friends you should know that they aren't really choosing that in the first place, and that's what feel right for them. It's not about procreation, it's just a matter of who you fancy.
As for celebrating it.. well, it's turned a bit ridiculous on occasions. I'm gay and I find it annoying sometimes. But the original idea isn't to celebrate your sexual orientation, it's the right to be able to be out, and that's not something that's always been there (and in some parts of the world still isn't), so it's more of a celebration of having that right.
Though there is the bit about normal displays of affection like holding hands or kissing, which straight couples can do without a second thought but if a gay couple does it some people do feel like it's shoving it into their face.







