There seems to be a marketing style which encourages children (or the adults who fund the children's habits) to collect toys for the sake of owning the whole collection, quite apart from playing with the toys. This is not a new idea, a 10 year old boy I knew over 20 years ago proudly showed me his model car collection, explaining he kept them in their original boxes, unplayed-with, because that would mean they kept their value.
It worries me that some marketing strategies exploit latent kleptomanic tendencies in humans. The most successful brands are the ones which become popular with great swathes of children, all trying to get the whole collection. If they are seen as 'cool' and desirable then a whole peer group will be collecting them. Monster High dolls were like this for one of my daughters, but she lacked the finance to really indulge in it. I think PM is trying to get Everdreamerz to become a popular, cool, collectable toy. If they are successful, that's a real gravy train right there...