When discount plastic cards were in use, it was not convenient to pass them on to each other. In some cases, this could deprive the privileges of the card holder. They were replaced by discounts on phone numbers. It became a little easier to exchange bonuses, but it was necessary to request a confirmation code from the owner of the discount. One of our clients, the largest Belarusian chain of fish and seafood stores “John Dory”, went the other way.
In their loyalty program, you can and should join family groups in order to save and spend bonus points together.