Why-house: Like Cellar Dweller, but with Warehouses.
Charity Worker: Buys Bishop solely for trashing.
"Get Rich Quick" Victim: Tries to get Golds with unsupported Transmutes or Treasure Maps instead of building up economy to just buy them.
And some broader categories:
Rat King: Always plays as many action cards as possible, even if they're likely to do more harm than good.
Try Everything: Buys some of every Kingdom card without any coherent plan to use them together (or variety rewarders).
Easy Reader: Ignores any cards with too much text, regardless of how simple they are in practice ("I have $5 and need more draw. I hear Journeyman is good for draw, but I can't be bothered to read all that text, so I'll just get a Smithy instead.").
The Berserker: Solely focused on playing as many Attacks as possible, ignoring things like greening and non-Attack payload (since those slow down the Attack engine). Because if I hit you with 8 Spy attacks per turn and you never score a hit on me, that means I'm winning, right?