Bondage is hardly about low self-esteem. It is about an exchange of power. In other word having so much power that you are confident that even when you are bound you are still OK.
I find that those who have low self esteem never want to give up power. The need the illusion of power in their attempts to gain what they never had. I have seen plenty of powerful people in life go in for to the ****** of bondage.
I myself am terrified with claustrophobia at the thought of being bound. While others love it.