My guess is that a lot of guys are so afraid of the idea that anyone might even think they're homosexual that they feel they have to make a big deal of how straight and macho they are. Even the very mention of anal sex is met with extremely vocal protest and outrage, because that's the shield they put up, and this reaction is continually fed by the reactions of other guys just like them. They're afraid that if their reaction isn't just a vehement as the rest of the guys, it will cast suspicion on them. All of which means that if a heterosexual man is seen as enjoying this sort of play, even if it's with his girlfriend/wife/etc, he's going against the code, as it were.

Now, naturally, I'm not aiming this at all heterosexual men. I don't even know if it covers most of them. But I've known plenty of guys who are like this, and they do tend to make their feelings on the matter known to everyone with ears.

Who knows where someone defined the rules of what is right or wrong during sex. I feel as if most men feel it is a intrusion on their dominance or masculinity leading it to be a taboo. Personally I could never understand that. While I feel that anal play can sometimes in certain settings revolve around a change in dominance it doesn't always need to be.

Speaking from a perspective of a male, I've also seen females disgusted by it. As in the idea of laying a finger on a mans as is vile. That in itself has perplexed me. I'm speaking from a perspective of a male who loves pegging, I've gotten to play with the fetish and it is possibly one of my favorite things. I'm straight, but it doesn't mean I can't take part in any type of anal play. I find it rewarding, stimulating and overall more arousing at times. When I have the chance to perform it it's honestly one of my biggest turn ons.

Not sure if it answers your question completely. xD

To be honest, I think most people are thinking of this in the wrong way... You are all thinking of it in a sexual light, but there are other (probably more likely and even better reasons) for why someone would think of it as disgusting.

To me, there are moments when I find it highly disgusting, and yet there are times when I find it very stimulating. It all depends on the situation and mood. But for others, it may be as you have described: they're worried about their dominance and their sexuality and what not. But, there are others still, who may be disgusted at it because of simply that: its disgusting to them. Its where all your 'waste' comes out from. Its considered one of the "dirtiest" areas of the body, so personally, its very understandable why alot of people would be against it. No one wants to think about having crap on their shaft or fingers.

So as I said, there are times where I enjoy anal play, and there are moments where if I happened to of thought about anal play in the way of being where your 'waste' comes from, I find it very disgusting and dont want any part of it.