How are points accounted for?

To our horror we realised that after all these years neither of us knew if there is a standard practise of recording for loyalty programme points in a company’s book of accounts! They do look like debts, albeit with some differences from ordinary debts:
1. The debtor can rescind or revaluate at any time, taking recourse to the small type (terms & conditions);
2. Not all points are redeemable, most being owned (actually, we don’t know who legally owns those points) by members below the redemption threshold; and
3. Not all redeemable points will be redeemed – some will forget, or never find the opportunity.

That’s about all I could think of.

Considering big loyalty programmes can easily carry points inventories worth millions, there must some standard methods for accounting them. I’d be obliged if someone could tell me about these, or direct me to a source.