[KarlKemp]

Merchants have no interest in allowing you spend you loyalty bucks with other retailers. Or they'd just give them to you in cash.

As always, cryptocurrencies add nothing useful to this scenario.

[teembeet]

Yes, it makes sense, but it's not so simple. First, it depends on how big is a merchant. Second, you will be able to pay only part of the product price with coins. Third, it depends on how big will be the demand for these coins.