For the same reason that some nights I want a coffee and other nights I want a Coke. I’ve learned I can drink either.
Then why wouldn't it be natural for homos to desire people of their sex? It would be natural.
You still have to explain to me why a person like Rock Hudson would choose ugly guys like Jim Nabors for "sex" rather than the numerous attractive females who would have been eager to engage Hudson in as much sex (regular or weird) as he liked.
How does a guy with normal sexual desires look at someone like Nabors and think "boy, I sure would like to get some of that." He wouldn't...unless someone had a gun pointed at his head or he thought Gomer was really some hot property. And you have to be really mentally twisted to think the latter. It's not like choosing coffee or coke...it's like choosing a delicious steak dinner or a meal of raw pig intestines.