It's illegal in the US too, with the exception of age-restricted (18+, 19+, 21+) professions like bar tending, selling firearms and ammunition or adult entertainment.

I think this site qualifies as "adult entertainment"

Personally, I'm fine with a reduction since any sanely written BT client will snub peers who aren't uploading much anyway. So even when people "leech" they're still contributing to the overall swarm speed while they're downloading.