Surely, anyway, this is based on the idea that we all share the same tastes, and that some tastes, because the majority don't share them, are in some way sick?
One goes into these situations with one's own prejudices and presumptions intact. For K9 (no, I'm not bitching, I think K9's opinion is perfectly valid and intelligent), with his/her stated views, to go into a BDSM scene would be, yes, 'sick' (his/her words, not my judgement). For someone who didn't see it this way, and simply saw it as good clean wholesome fun, to go into a BDSM scene would not be the sign of a sick anything.
/Me forgets what point me is trying to make
Different strokes for different folks. For me to indulge in perfectly 'normal' heterosexual sex, with the lights turned off and in the missionary position, of course, would, to my mind, be the sign of a sick society. Sign of male dominance, compulsory heterosexuality, my own self-destructive urges, whatever. Presumably, to your average perfectly normal vanilla heterosexual, wouldn't see it this way. But then, I'd see them as playing out a microcosm of sexism, homophobia and sheer, unadulterated, boredom and apathy. (Do me a favour and don't vote me down because you don't agree with this premise. It's an example, not something I think should hold true for everyone). Sadomasochism, as far as I'm concerned, is the sign of a society comfortable with its desires, and not desperate to hide behind 'natural' and 'normal' activities.