Gay guys are usually more body conscious and physique obsessed than straight men. The market scene for us is much more competive and intense than the hetero search-for-a-mate scene.
But when you look at the homosexual lifestyle overall, it is not just the gym efforts aspect that gay men do to such extremes. Gay men are usually more educated than straight men, usually make more money than straight men, usually travel and have greater culture experiences than straight men, usually have much nice homes, etc.. which isn't a flame, it is simply because gay men have more disposable time and income with not having child raising restrictions and expenses. In the gay world a divorce consists of you getting your shit and getting out. Not you getting your shit and half of your ex's. No alimony, no child support, no baggage.
P.S. If you want to see a gay bodybuilder, look at the last two Olympia lineups, there is a very VERY gay bodybuilder that finished in the top 5.