Actually, lets take your logic to its natural and hilarious conclusion: Donald and Eric Trump wearing Brady NFL jerseys getting a locker room pass to suck off Tom Brady and 'deflate his balls (hyuh hyuh)' because Brady is their sports hero...
Just something we straight dudes don't tell Melania and Lara about--wink wink!
All I am saying is that there are “some straight” guys who are so attracted to other straight (or gay) guys that they would provide hand jobs, blow jobs, or even bottom for them.
In such cases gay sex may not the driving motivation. Gay for pay is a special case of this behavior where money is more important than any aversion to same sex activity.
I have introduced this line of thinking in order to compliment and expand on the OP’s effort clarify why one (straight) person would give another person a BJ. An underlying assumption here is that gays do this for pleasure (usually sexual). I
totally understand how the OP might have made that assumption.
But what I am trying to say is that just by putting a label on it and calling it GAY because of its popularity among gays leaves a lot to be explained in terms of human dynamics.
For example, if Richard Dawkins were to offer to give the Pope a blowjob during the next NFL Super bowl halftime show just to prove that he would not be struck dead, I wouldn’t find my self focused on Dawkins need for sexual pleasure. In that circumstance, it wouldn’t be a gay act.