BDSM is an aberration. It should not be promoted as any kind of normal sex. It should be recognized as belonging to very special people. Once abnormality is accepted a normal behavior, it doesn't stop until the society becomes wholly depraved.
BSDM isn't a "kind" of sex.
There actually doesn't have to be any sex involved at all.
this is also true. And apparently you know more about BDSM than the author of 50 Shades.
I've known a number of people who've worked as professional Doms.