Yes, an exit node operator will appear as the source of the traffic, which can have legal repercussions. (Personal risk.) But on a macro scale, the entire Tor

Yes, an exit node operator will appear as the source of the traffic, which can have legal repercussions. (Personal risk.) But on a macro scale, the entire Tor network has fairly limited bandwidth and torrenting is a very easy way to saturate it. (Existential risk to the network / tragedy of the commons)