Well I read books over and over so keep them forever! I have trouble getting rid of books even if I hated them, which is fast becoming a problem!
But if I wanted to get rid of some books I'd probably just donate them to nursing home, community centre, schools, libraries, hospitals, day centres for adults (I can't think of the actual name but places where adults go for the day for respite and therapy) to name a few.

Or you could sell them at your local market? Then you wouldn't have to bother with fees etc.