Isn't it kind of a middle-man service so you don't get narc'd on by your ISP for large amounts of p2p traffic? That way all your ISP sees is you downloading data from one source rather than lots of.p2p traffic.
Unless you use vpn obviously, that doesn't have issues with p2p traffic or whatever.
A few months ago they got told to quit it so they were like "oh shit apparently there are PIRATES using our piracy service. We never wanted THOSE GUYS as our customers!" and started neutering piracy, which was clearly their main source of income.