Actually this is complete bullshit. Torrent'ing in no way "help ISPs".
The shear number of connections a single person generates by downloading using torrents is ridiculous. It is basically a legal DDoS (well depending on what your downloading). The problems from bittorrent isn't because of the bandwidth used, it is from the number of connections.
The number of connections is completely irrelevant to any proper ISP (i.e. one which isn't NATting or snooping on your traffic): 100 packets per second on a single TCP connection is precisely the same traffic as 1 packet per second on each of 100 connections, except that it may spread out across more peering/transit links. My ISP literally does not know, let alone care, how many TCP connections I have open right now - only how many packets and how many bytes I'm transferring each way. It does indeed benefit my ISP if more of my traffic is local, since that means it can go via cheaper peering links at LoNAP or LINX rather than the expensive Level3 global transit they use for routing to/from more remote networks.
Where it does matter, though, is your home router/firewall/NAT device, which does need to keep track of each and every connection while it's active: a hundred or so connections might well overwhelm the available state storage long before you run out of bandwidth. On that level, downloading a single file is the same whether it comes from the ISP itself or another continent.
Of course, some ISPs are more clueful than others; mine is not only entirely happy for us to run torrent, servers (official policy: do whatever you like except spam; copyright and other issues are up to the police/courts not your ISP) but are even considering hosting their own Tor exit node. No shaping or filtering except the overall bandwidth limit - which caused packet loss for 0.83% of the last week. If only all ISPs could run like that!