American Dad and Family Guy: We Love Used Car Salesmen!

Used car salesmen…is there anything they CAN’T do? Because they figured extremely prominently in both American Dad and Family Guy tonight:

Stan from American Dad lost his ability to negotiate after being suckered into what, 10 cars? by some greasy used car salesmen.
And Peter from Family Guy got suckered into buying a tank for Meg after he forgot to pick her up at the roller rink with his drunk buddies…and then plowed down the American Superstore, aka Wal-Mart.