How About Zero Shades of Grey??

I am very upset today. Last night, I read a brief article about the book--(that obviously everyone has read but me) Fifty Shades of Grey. It was just a brief article in the Atlantic, something about humans escaping numbness.....but it wasn't this article that bothered me --as the glimpse it gave into the newly popular erotica.
The author gave some examples of the "new sex" I am supposed to be all hot about. I mean nipple clamps?? Try breastfeeding a baby with teeth!
Or what is with the orgasmic spanking? Is this really what women want?? We have spent so many hundreds of years getting men to STOP hitting and abusing women. And now some crazy lady writes a book that women want this?? But the truly bothersome thing isn't the weird author--but the well known fact that millions of real women are reading this book and liking it. 
So that leaves me really confused. Am I weird? (I am no prude, took human sexuality classes in Graduate school). And I would quite honestly slap any man who tried to spank me, then get up and leave him for good. So what is with these women? Are they freaking crazy? (my husband claims they are dumb, and just trying to conform).

I always assumed, that people who want to be abused for pleasure, have psychological problems (i.e. self hatred). Like teen girls who cut themselves.  As I did spend time studying human sexual behavior in school, I can safely say there are many parallels between animal sex and our own human kind. Many behaviors could be considered biologically "normal"--including homosexuality and rape. But wanting to feel pain??  Not normal. (being dominated makes sense, but not the pain).  Even a guinea pig or rabbit WILL BITE a partner that tries to mount her when she is not in heat (and thus uncomfortable) during intercourse. For crying out loud, brainless worms know better than to seek out pain. I still remember our 7th grade science lab, where we poked poor worms to elicit their "pain response" and we would write down in our little notebooks--"that the worm had the common sense to recoil from the painful prodding."  But I guess today's modern women do not.