Every person who has a hobby or does crafts has lots of material to work with. Carpenters have stacks of wood, artists have several different kinds (and lots) of paint and canvases, hunters have lots of guns and ammo, fishermen have lots of lures and rods and reels, etc. etc.
So it only stands to reason that a knitter would have lots of yarn. I say it's high time we stop making excuses for it and embrace this fact!