||I think what he means is, why is it often deemed more socially and morally acceptable to make jokes about homosexual rape than heterosexual rape? I's a valid question, and the ideal answer would be "it isn't". Unfortunately, that doesn't seem to be the case.
Well, if you're putting it like that, I suppose you have to consider the audience. Women are sensitive creatures and aren't going to find any sort of rape particularly funny. Men might find both kinds funny, but they can't laugh so much at hetero rape (ie men raping women) because of the moral campaigning done throughout the country against it. They can't laugh at men hitting women or racist jokes for much the same reason.
However, men raping men is a kind of loophole, as is women hitting men, or the same way you can laugh at the Bhangra-man or Ali G taking the piss out of their respective stereotypes without feeling like a white supremacist.
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