In my country prices are often wrong because supermarkets are run by a small team of literal teenagers (one of the downsides of having decent minimum wages is that nobody wants to hire anyone if they somehow can avoid it).
It's definitely possible for a job to have negative expected value for the employee, even if looking only at cash flow. MLMs are the most obvious way, but e.g. hairdressers often need to rent their station in the store -- while this can be a reasonable deal, it can also run negative.