The Japanese English “campaign”・キャンペーン means a kind of “promotion”.
Most of the campaigns are discounted prices for limited times. introductory offers for new customers… but…
Many companies are offering “prize campaigns” – if you buy the selected products you can collect stamps/stickers and cash them in for a chance at a raffle.
The latest Pokemon themed campaign sees you scanning two ketchup-product codes to enter for a chance to win.
The biggest prize is a giant Pikachu sleeping on a ketchup bottle pillow that 2 lucky people will become the proud owners of.
Check out the campaign page here.
Many big companies cash in on this kind of marketing.
Coca Cola Japan also ran a popular summer prize campaign in 2013 to win beach goods:
Another common campaign is collecting stickers on products to trade in for a guaranteed prize.
The most well-known is convenience store chain Lawson – if you buy packaged bread you can collect stamps for Rilakkuma, Snoopy or other cute characters.
Usually a sandwich or small roll is one stamp but bigger packs like cakes have 2 or 3 stamps.
If you collect the full stamp card (20 or 30 stamps) you can hand it in to the staff and get a bowl, cup or similar limited-edition prize.
(You can’t actually buy the bowl, even though it’s on display. Only through
blood, sweat and tears eating lots of bread can you earn it!)