Sometimes if I like something alot I will watch it a 100 times and buy the dvd though at that piont I do not want to watch anymore becuase I have seen it a hudred times but I will still buy it and all others in the set just to have the collection . Though alot of the times I just buy it for the collectors value even if i do not want all of them and they are real cheap or on sale Ill get them just becuase I want to be able to say i have the whole collection even if I never ever toach the iteam again . i have done that with alot of things in the past .

This sense is exploited in small children by the sale of trading cards such as Pokémon, and exploited in large children (like dappled) by the sale of football stickers such as Panini. It's also one of the many tricks used to keep people playing computer games, like World of Warcraft.