Did an essay on this. Don't find it exactly fine.
But since writing that essay gave me a headache, I'll break down the why's:
In most canon media, the assumed straight people vastly outnumber the proven gay people. And I say 'assumed straight' and 'proven gay', because being straight is default, where-as a character has to admit a definitely solid statement they're gay to even be called gay.
You're only proven straight if you say, "I'd NEVER sleep with a guy/girl." And you're only assumed gay if they simply act it (unless the creator specifically admits said sexuality). Not to mention, heterosexuality can easily be used (in fantasy or real life) to hide your homosexuality (and when is it ever used in reverse?). Which personally explains why I like poking at Brock's overenthusiasm. *snicker*
That, and breaking up the gay canon couples is...like.....I dunno, heinous or something, since given all the straight couples you could dabble with, why ruin what little slashers can call their own?