Variety is the billable part
A proposal in the open standard for cloud billing would record, for every metered token, whether it was read from a cache, written into one, or neither. It is four words in a schema. It is also the first place the industry has written down that the cheapest system is the one that repeats itself.
Token caching has made the changing part of a request the part you pay full rate for, and the billing standard now being drafted turns that ratio into a target before anyone argued that sameness is a property systems should be designed for.