I don't think hoarding is greedy, because I don't think hoarders necessarily buy anymore than anyone else. This varies a lot, some do, and you see them on Hoarders with the unopened boxes from Ebay I guess. But that varies.

What hoarders do is they refuse to get rid of (by one way or other) things others do get rid of and so they might accumulate more over time (ok and some people may not even accumulate any more than anyone else, but just have an organization problem, they either need to be organized like other people with the same amount of stuff are, or own less than others).