Montreal Mirror: "Freebies for overcharged customers
Attention all Quebec shoppers! Freebies await if you keep an eagle eye on cashiers ringing up your bill. That's because retailers in la belle province - unlike those elsewhere in Canada - are forced to hand over a product gratis to any customer who notices that he's been charged higher than the posted price on an item costing $10 or less. Any overcharged item above 10 bucks immediately gets reduced by a tenner."