Presumably their concern is someone creating 10 free accounts, and pooling/using them simultaneously. If their software and website (at the same time) supported any number of paid accounts with at most one free account then neither you nor I would be harmed.
I think I have about 40GB of free storage with DB as a result of working there referral system. However, a friend bought some Android based phone, came with DB pre-installed, and he has something like 500GB or free storage. They were doing some promotion.
I think one of the main issues with DB is that it is too little space and too much cost to add more. Considering what they pay for bandwidth, any paid plan really should be unlimited.
