Reduction also for some magazines, and more importantly for plane tickets. CJP is also valid in other European countries. Some of these countries have their own reduction cards which are equivalent to CJP and which are also valid in Belgium. It is valid in 90 countries. You can usually buy those cards in travel agencies.
Some supermarkets have their own reduction cards.
Some give you a percentage on what you buy. In other supermarkets you can save up points which can be converted into paychecks. But anyway, those supermarkets that don't give any reduction are sometimes still the cheapest. Clothing Boutiques are usually the most expensive places to buy your clothes. Prices there are usually lower than in the supermarkets.