@pkrowiak @georgepenney I didn't do anything like this, but I did just leave a whole bunch of groceries on a self-checkout machine when it started saying I was blocking something and insisted I couldn't carry on until a staff member came over to "help".

I gave it 15 seconds, and when the staffer wasn't there yet, I walked away, past the staffer that was finally approaching. "You want self-checkout: try self-payment now. I'm not buying this anymore."

Never used self-checkout again after that.