The people saying that are either idiots or private tracker snobs. VPNs are absolutely an important part of shielding yourself from any potential legal action, particularly if you are torrenting.
It's true that a VPN doesn't make you or your activity completely anonymous - you are trusting the logging policy of your provider - and won't necessarily protect you against a court order, for example. However the only realistic danger to a small scale pirate such as yourself is the copyright troll who traces torrent IP addresses back to your ISP, thereby identifying you. If you mask your IP address with a VPN, you prevent them from doing this efficiently and effectively protect yourself from the threat of legal action.