I think you may have misunderstood the comment. In the US, Ireland, and probably elsewhere, police are using rogue cell sites ("Stingrays") for surveillance. The person you replied to is claiming that this is illegal, and the police forces that are doing it should be punished. They weren't talking about people experimenting with setting up Faraday-caged toy cell sites in their basement — there's absolutely nothing wrong with that and it should be encouraged!