I'm not too much of a hoarder... but my GF thinks so.
To me, a hoarder is like the above example, keeping crap for an eternity. Buying 10 pairs of pants is something else entirely, though probably no less crazy in the long run.
For example, I have probably 5 backpacks for camping, a dozen knives, and about a dozen flashlights. Am I hoarding? No... cuz I try to sell them every few months to get more of my money back to get new ones!