Nonsense. All humans have the urge to
dominate,
submit, and inflict or receive
pain locked down tight somewhere in the basement of their minds. A
healthy society finds ways to create
safe outlets for these feelings.
If anything, BDSM allows people to express their desires for domination and/or submission, sadism and/or masochism in a socially healthy way. If these urges were not expressed sexually, with the full consent of the partners involved, then they would most likely manifest themselves in other, destructive forms, such as:
A: Neurosis, brought about by bottling up these "bad", "naughty", "wrong" and "shameful" feelings. Preventing expression of desire doesn't make it magically disappear and can, instead, severely damage a person psychologically.
B: Sociopathy. The need to dominate could be expressed by intimidating and/or attacking innocent people. The desire to submit to control can, left unchecked, lead to dissolution of identity and absorption into a hive-mind. And, clearly, we don't need people wandering around with the need to inflict pain on passersby.
Sex is a Dionysian outlet. It allows us to set aside our rational selves, the selves that we need to live in a society, and exult in the Id. Sublimating those desires we can't express socially into sex play (the reverse of the classic definition of sublimation) allows us to blow off steam, so to speak. Assuming, of course, both partners are consenting.
I, personally, believe that the existence and acceptance of consensual BDSM, and other "kinky" sex play, is the sign of a society healthy enough to know how to deal with the darker sides of its members.