Oh My Gawd, (see what I did there?) I can't believe that stupidity such-as-that is accepted, let alone 'tolerated'. As far as I'm concerned, that being the job this broad has, she should be fired on the spot.
After all, if someone ISN'T capable of doing the job that they were hired for, AND WE UNWILLING TO BE TRAINED let alone 'corrected', then they should not have that position.
There's plenty of shopping-carts out there, that need inhabitants.