Politeness is not a problem. You can be very polite and still insist on doing what you want. You just need to realize the person who's selling you crap is not y

Politeness is not a problem. You can be very polite and still insist on doing what you want. You just need to realize the person who's selling you crap is not your friend and you don't owe them anything, and politely refuse to take it. Saying "no, I do not want this, thank you" is not impolite.