It's a bullshit job though. Do you refuse to use elevators because they no longer have attendants? Having worked on a checkout at one time, it was always depressing. Plus there were other tasks that could be done and most people you deal with are awful.
People making the same old quips also make the job that little bit more unbearable - "must be free", urgh. Seriously you are not gods gift to comedy with these jokes, workers hear them 100 times every day and it is like some kind of compounding psychological damage each time.