Within a certain strain of the culture, there is no fear of death. My best friend is a doctor who works in a university clinic, and he sees a fair number of gay students. It really shocked him at the number who automatically assume that they won't live past 40, and won't listen to his recommendations on health because they are only expecting to live 15-20 more years.
The Rump Rangers ride again.
The kind of madness that Paul of Taurus talks about in his letter to the Romans.
The idea that gays lose themselves in self-destructive mindless hedonism to drown out the pain of being rejected by society is a common theme these days. I think it also has to to with the male sex drive being multiplied by two. If all the girls I knew in college were as willing as the guys, it would have been a real mess.
Part of it may be that they don't WANT to live past the point where they're too old to be sexually attractive to other gays. Remember, for many, the promiscuous party scene is the only life they know