A good rule of thumb when trying to sell things: If you think a potential customer may not have much money, and you're especially polite to them anyway, that's a good thing. If you think they may not have much money and you're rude to them, that's a bad thing. These two effects are magnified if you guess wrong: especial politeness to a customer who turns out to have money will make them happy. Especial rudeness to a customer who turns out to have money will make them take their money elsewhere.
On a completely unrelated note, if you're ever buying a car, you may want to give Stevens Creek Acura in San Jose a miss.