This is sort of a double edged sword thing, so let me put my few cents in.
matter.
They should just allow the TTL as it is, and let some keep it high, and some put it low, in my opinion, because 5 hops is nothing. I live in CA, and most places anywhere past arizona are more than 5 routers away from me. Sure, I probably don't need files from 2000 miles away, but what if it's the only way I can get that song I *really* want? If you notice on the list of connections, most people sharing lots of files set their TTL high anyway.
The amount of reflected packets and packets that loop forever, etc. can't be worth the expense of finding faraway files, especially since the amount of subnets the packets can get lost in is so many that it can't really hurt the "network" that much, can it? (Feel free to share your insights if I'm wrong)