This looks like a marketing usage. It sounds as if the mobile telephony provider is offering some service that, although it involves downloading some data - say, a weather forecast - does not affect that subscriber's normal fee for downloading data; perhaps their contract allows the downloading of 1Gb a month free, and after that they have to pay - the service advertised doesn't affect that month's credit. (I don't know for sure, I'm not much of a mobile phone user. But it sounds to me like the sort of offering such companies would make.)
b