What's the point? What advantage?

This is perhaps the most nonsensical loyalty scheme I have ever come across. Nearly all businesses nowadays encourage you to take out their membership cards to collect points or stamps to pay towards something nice later. All the other cards I have allow you to use the points as part payment, or they have a set of items as rewards so you know what you can have for how many points. Boots Advantage Card is the only scheme I know that does not work this way. As Boots does not offer the best prices, I cannot see any advantage of shopping there, nor can I see any points in collecting points on the card.