I think if you're a hard-core collector and need to have a physical case to display to show you own the game, as long as the cases aren't a stupid amount, then I see no issue with owning them. It's not quite the same, but I purchased some repro cases for my Dragon Quest DS games since they came with the game only (thanks GameStop.) I like having them to display like a personal library on a shelf for all to see. Much like people used to do, and still do, with leather-bound books.