Why isn't Woody a valuable item anymore?

In Toy Story 2, Woody is a highly valuable collectible, but in Toy Story 3 this isn't true anymore. We know Andy has internet on his room, so he could check for his toys' price easily, but it seems that they have no monetary value in Toy Story 3. For example, In a scene when Andy is packing his stuff before going to college, Ham says he is going to check the toy's value on ebay in a tone that indirectly says "we are worthless". In another scene, Andy says they are just trash, and at the end of the movie, Andy gives Woody to the little girl just considering the emotional value. So, something had to happen between Toy Story 2 and Toy Story 3 to turn Woody from a "collector's treasure" into "trash".