Worst job I ever had was being a telemarketer. Cold calling people all over the country all day for a shytty product where I knew the company was screwing people over, and having to get cursed out about once an hour for calling these people.
But to me the worst job to have is a nightclub bathroom attendant. Nothing can be worse than running a faucet for dudes just to get a tip, and grabbing paper towels for them and shyt, while they shyt on you for having the audacity to ask for a tip for running the water when they could have done so themselves.