I would also say that this is because anonimity is not needed by all countries. I know that in Spain torrenting is not a big issue and ISPs don't care that much (even though distributed Copyrighted content is still not allowed). They usually go after people profiting from distributing copyrighted company rather than people downloading or distributing for free.
Disclaimer: I think some of my info is a bit outdated so if anyone has more recent info about Spain's situation please tell me.