He doesn't want to be your friend, he wants to take advantage of you. If people support him in that, then they also want to take advantage of you. Telling someone to pay for your services is not rude, it's good business. Tell him to pay up or look into taking legal action.

This guy is wasting time you could spend on a decent customer.

I have 2 older brothers and they would never treat me this way. They know this is my work; they get paid for their work and I deserve to get paid for mine.