Amazon Prime may promise lightning-fast shipping and countless perks, but according to U.S. federal regulators, millions of customers got more than they put in their shopping baskets. Even more troubling, in some cases they signed up without fully realizing it. Now the online giant is paying a massive price: a record-breaking $2.5 billion settlement. That includes$1.5 billion in refunds for Prime members and another $1 billion in civil penalties. The Federal Trade Commission (FTC) says Amazon tricked pe ...