This was a nice quiz that I enjoyed taking. I think the hints for the cars should be changed to "Location" like most of the others, especially since "car" is an acceptable type-in for all three answers.
I suggest more type ins for most of these. For example, if supermarket works for Marge, should also work for Maggie. Checkstand is not a common term in my region of the US either, and I tried checkout lane and scanner, I would suggest either letting more specific options work for maggie, or to let grocery store/supermarket/trynsave work.
Station wagon should work for orange station wagon, especially if car works for pink sedan.
Also tried lots of things like conveyor, bag, trolley, checkout, supermarket etc for Maggie first appearance
Edited to add..just watched the intro sequence on Youtube and I take back the Chief comment above...sorry
Station wagon should work for orange station wagon, especially if car works for pink sedan.
Maybe add Barney on the sidewalk too :)