Buying internet logs might also be highly illegal in the EU, but IANAL
Because an IP address is not a mailing address. And they don't buy your internet activity logs. They buy the ISP's log of which IP was associated with which account.
If it was the police uploading a new torrent and getting people to download it, it might be.
If it’s a private firm that joins the swarm and observes who is seeding, it’s different. They don’t even need to seed anything. Nor download anything. But even if they did it might be ok.
IANAL, TINLA.
You can either join private trackers where they're not allowed to hang out, use a VPN to make you "untraceable" (as far as these petty tyrants are concerned), or both.