And finally....he said that when he was a young man, he knew another young man who was gay. He said he himself was not gay or bi in any way, but that sometimes he would "use the young man like a woman". This was apparently not uncommon. He said this was how a lot of gay men were able to have frequent sex, since being gay was totally taboo still when he was young. But it was known that a certain percentage of men were gay so there was a sort of arrangement made between horny straight guys and gay guys where the horny straight guy could get off and the gay guy would just give. There was no confusion about whether the straight guy was straight or not, he was. And there was no confusion of whether or not the gay guy was gay, he was, and he knew the straight guys were straight.
This is not uncommon here in the US, either.
I live in the midwest. We're fairly conservative and very blue collar round here. Yet, if you drive down a certain road in a very populated area you will see a nondescript building labeled as a men's health club. Inside, you can get a year membership for about $40 and pay $10 a visit. There are sauna's, a pool, a locker room, showers, TV's showing gay porn, benches and private or semi-private rooms with men having all forms of sex with each other, and even a room that looks like something out of Arabian Nights. It's a bathhouse. And, even in the age of the online NSA hook-up, it's parking lot is PACKED in the evening, late night, and early morning.
I've known men who have gone there. The majority of those guys are straight and will tell anyone who asks that they are straight. They believe themselves to be straight. But they are desperate
for sexual contact with another human, cannot find a female partner for some reason (usually married), and come to this in-person anonymous place to get an easy handy or a BJ and then go home. Typically, the horny gay or truly bi guys give and the straight guys receive without reciprocating. True ships passing in the night stuff. Two (or more) guys sit or hang out in an area, catch each other's eye, do whatever they are into, and part ways. No names, no muss, no fuss, no drama.
I knew guys in HS who were openly gay and passed out BJ's like candy to the straight guys who never had oral before and/or who were desperately horny.
I've seen straight women get all loopy emotional after a divorce or LTR break up accept all kinds of attention and affection from another woman, including receiving oral. They're in a bad place, need the comfort.
It seems for both genders, those who identify as hetero but have had sexual contact with same sex partners do it for the same reasons. A desperate need for the touch of another person, the sexual release, to feel desirable/accepted by another human are the primary motivations, not sexual attraction to the same sex.