How does it feel to feel?

Tony Moseley, the artist of Zogonia (www.zogonia.com) posed an interesting question today: At what point does an adventuring party bring more loot into the dungeon than bring out of? He thinks level 11. If Richard was DMing it'd be level 20 (maybe), but I think for regular campaigns you should hit that threshold at about level 9, presuming you kept all the stuff you were given.