Will return with new account. Best action to warn member will blacklist his shop address on bitcointalk if repetitive behavior. Rule say unsolicited personal message advertising will a ban. Can make to newbie we can not send personal message.
If they return with a new account after getting banned. It will be considered as ban evasion and it will be banned too. Secondly they will be wasting time here trying to spam in the name of advertising if members are well aware of their unethical behavior. No sane forum member would want to use their service after seeing their shady tactics.