Presumably it's because they expect you to put it towards another data bundle, within a few days (10 days, I'd think, based on my experience), so it keeps feeding the monster.
The previous way they ran it, made it easy to use data for 60 days, then recharge with a new package, whenever you wanted to - as long as the SIM didn't expire ; even then could just get a new one, but this way, if you don't want to lose your rollover data you need to keep loading airtime / converting to data bundles within 10 days, I think.
The previous way they ran it, made it easy to use data for 60 days, then recharge with a new package, whenever you wanted to - as long as the SIM didn't expire ; even then could just get a new one, but this way, if you don't want to lose your rollover data you need to keep loading airtime / converting to data bundles within 10 days, I think.