Why I am buying books only to sell later ? How to overcome this ?

Over last 6 months, I have developed a habit where I would order 6-7 books every month. I would search for these books on internet. For example lists like 'must read books' , 'most recommended books' etc. But once these books arrives at my home, again I feel a compulsion to discard them. I start to feel that these are boring books or not so good books. Then I would go to some shops which buy these books at a much lower price. And the cycle repeats. 

I know that buying lots of books when already books are available is a normal behaviour. But the fact that as soon as I get these books, I feel compelled to discard most of them. This behaviour is worrisome. What can be the reason for this ?