Some of it is due to laws or regulations (some federal, some provincial), and some of it due to thin profit margin. In our business, our loyalty card (Shoppers Drug Mart Optimum) we are prohibited by law from awarding points on tobacco and over-the-counter codeine purchases. Some provinces prohibit awarding points on prescription purchases. We don't award points on lottery, stamps, bus tickets, etc because of the almost zero profit. There you go, and no I'm not a lawyer, just a lowly pharmacist.