There is something more, well, arse like about the heterosexual male's arse. The culture assigns it quite different properties to that of it's female counterpart. The arse of a straight man is hairy and smelly, gaseous and not to be messed with. The female arse is merely another hole, so surely it needs a dick sticking in it. In fact, if there's a camera rolling, maybe it's begging for two?
Anyone would think that the male and female of our species had entirely different digestive systems. In fact, the only discernible differences are that a) the male is hairier (and even that's debatable) and b) the male, as so expertly described by amboabe, has the added sensory advantage of a prostate gland.
Mainstream hetero porn is obsessed with images of a wide open asshole. A strange disembodied spectacle that barely seems sexual at all. It smacks of chest beating "corrr, look what I can do" rather than any kind of sensual experience.
It's all about power.
This macho stinking "don't touch it because it might explode" male arse can conveniently, when faced with an intruder, go all Southern Belle a la Gone With the Wind (pun intended) and all but (he he) scream "I do deh-clare!". Now this delicate little flower can scarcely unclench itself, much less allow a woman to investigate it.
Bottom line (you know, I am trying to stop), the one doing the penetrating has the power and he isn't about to relinquish it. But what does that say about the state of the relationship? If it's a one night stand or a short term thing, why the fuck should you care who's in charge? And if it's a long term thing, surely the machismo can stop?
So come on gentlemen. Take a leaf out of Amboabe's book, get a grip on your masculinity and loosen up. (Sorry, couldn't help myself)