So make 'em include the tax amount and percentage in big print on the receipt or alongside the price on the price tag at some percentage the size & weight of th

So make 'em include the tax amount and percentage in big print on the receipt or alongside the price on the price tag at some percentage the size & weight of the price itself. Both problems solved. Paying a different price at checkout than what was on the tag is dumb and provides cover for exactly this kind of fiddling-with-the-price crap.