And even camming, believe it or not. (If this
http://www.lpsg.org/111712-straight-guy-loves-compare-other.html is the same guy.)
I've had straight guys cam for me (no actually, more like TO me or AT me). They are very different to gay or bi men. They are not interested in seeing my cock (I don't have a cam and they're happy with one-way). They get off on my admiration of their penis rather than dirty talk or gay sexual fantasising. Any chat about sexual activity is about them and their woman, and they talk about their wife or g/f in an open but respectful way. They are not at all interested in what I get up to with my partners.
I don't fully understand what they get out of it. I sometimes think they'd be happier showing to another straight man, if they could find one that was interested. But it seems to affirm them.