I think you've raised an excellent point here.

Loans (interest, and also contracts in general) are not required to be presented at a level that /most/ of the population can understand. There is a giant, thick, legal language contract that even if you are a lawyer you probably don't really understand (it hasn't been adjudicated, so you don't know what a judge feels it says).

Disclosure: I do use credit cards, but only as a convenient and insurance providing mechanism for accessing my bank account and recouping some of the fees built in to prices by the predatory banking industry.