It's true - something always ends up going wrong using those crap things. Then you have to wait for a Real Live Person anyways! Screw that. It's hardly a convenience, but I guess the incentive is to make checkout faster, so the discount, yeah, it would kindof defeat that purpose - muck up the lines, wait longer ect. What they should really do is get some more 15 items or less express lanes, or 20 items or less. Something like that. Those go pretty quick and you get the benefit of a checker doing what they get paid to do.