There is a further difference in that these things can, for the most part, be done in moderation without substantial adverse consequences. The same cannot be said for homosexual activities. Just one gay encounter can cause any or all of the harmful effects listed. It's a matter of degree of danger IMHO. And let's not forget that innocent people, like spouses and girlfriends of bisexuals, are also put at risk by these activities.
And there's the NAMBLA homosexual pedophiles attempting to lower the age of legal homosexual sex with children down to the age of 10 years old.