I think that many of these guys are just sex addicts, and sex addicts will have sex with anything to satisfy their compulsion. For example, Brazilian porn model Gabriel D'Alessandro was featured on Doctor Phil's TV show a couple of years ago, saying that the is straight but will sleep with anything that's available, because he cannot help himself (by the way, the show featured his alcoholic wife and his two little children... Seriously?). Also, we should remember that they are prostitutes, and they must market themselves in a particular way in order to ensure that their client pool is as wide-ranging as possible.
Still, I find it funny how many of them label their sexuality dozens of times in different ways and then, get incredibly upset when people ask them about it.
For example, Austin Wolf constantly yaks about being bisexual, how awesome women are and how he'd have liked to marry one, but then gets into hissy fits when his creepy female fans tell him that they'd like to have a relationship with him and proudly declares himself to be "a homosexual". Really? Talk about cognitive dissonance.
The same is applicable to Logan Moore, who said that he would love to do bi porn because he likes women (as R126 has mentioned), but then got all upset when some of his fans asked him why he pretended to be gay if he is bisexual, and promptly deleted the tweet. As for Theo Ford, he went to The Daily Telegraph last year to declare himself a "five star gay" who is married to a guy and then, started blabbering about being "interested" in women.
I also read in Dani Robles and Flex Xtremmo's twitter that they like to frequently have sex with women but "only when other men are present" and thus, that somehow makes them gay... Really? That is an interesting way of seeing things.
You also get these gay porn stars who claim to be gay but have always been bisexual, like Vinnie d'Angelo, Boomer Banks, Trenton Ducati or Ryan Rose, even though they are irrelevant now.
By the way, regarding Arpad Miklos, he killed himself because he was seriously depressed: he was pushing 50, still working as an escort and facing lots of competition from younger guys, didn't have any significant assets to his name, had definitely broken with his on and off boyfriend of many years, seroconverted and found himself struggling financially because, while he had worked steadily in porn for many years, his silly "straight-for-pay" venture had proven disastrous for his image and he wasn't getting any work when he needed it the most. His situation was really tough, in short. I also remember an interview in which he said that he hadn't any family left, so I guess that he must have felt really alone.
Anyway, gay porn stars are peculiar individuals - incredibly uninhibited for things that would shock most people, but extremely conflicted about the most basic stuff.