Registering the trademark won’t let piracy particularly because those who want to register their trade mark will be required to perform a search before the registration. Registration of your trademarks proves its virtue here.

While searching, your trademark will appear in the list, provided you registered it, and will discourage them from using it or even something distantly similar to it! If the trademark registering authority finds a registration seeking trademark at least confusing with an already existing one, they won’t let its registration.