The reason they don't offer compensation is because they know there will be a lot of claims. That will cost them a lot of money.

For the Ultimate Reservation Guarantee, not many people make the claims. It is just too awkward to do so. And how do you "prove" that you made the claim? And I am sure once a hotel has to pay out, they learn their lesson and will really teach staff to proactively offer the benefits. This is why the benefit sticks - few people are able to claim it.