Frustrating time at the Bookstore!

Since I have been going through things upstairs, I found that I have about twenty books that I would like to get rid of in one way or another. Some of them are old college textbooks, which I will not get any money for, but some are recent homeschool books that I could get some money for. I decided to take all of the books yesterday to a local bookstore and see what they would give me for them. I specifically knew on a few of them what I could get for them online, so I sort of had a price in my head. I gave them all twenty books and waited 45 minutes to give me an offer. Guess what my offer was?? $4.50!!! FOR ALL OF THEM!! I was rather shocked and mad. I told them I will NOT take their offer, grabbed my books, and left. I was rather frustrated! I could hardly believe they gave me such a low offer! I know some textbooks were old and I expected that, but there were 15 other books that were worth something. I brought them all back home (the children helped me carry them all again!) and started looking them up on ebay. Sure enough, they are going for a decent amount on ebay. Ugh. I guess I should start listing them there!