The main 'fun' of being a submissive is that one doesn't have any responsibilities any more. So people with escapist frame of mind love it. Also someone who is tired of responsibilities thrown at them,or simply wants to shun them, love being a submissive.
The entire body and mind is under the 'control' of someone else and one doesn't have to think about anything any more. It gives one a denial. I am all bound and I'm a slave, I can't look after myself how am I supposed to do anything else?