The right to freely trade is a basic right, as is the right to refuse!!!
I'm not sure about the right to refuse. If you refuse to give service to someone, for example, because they're black, that's discrimination and a crime in certain jurisdictions (it should be everywhere).
Are you serious??
Can you imagine.....
excuse me sir, are you refusing to take my money/coins??, I will see you in jail sir because holy hell you not buying from me after you met me is down right illegal!!!