Runtime checks aren't an impossible effort to defeat either. If you're into this stuff, you should build a plugin with them yourself and then figure out how to crack it. It's a great learning exercise.

As another commenter wrote, the protection is there to keep honest people honest, like locking the front door of your house.

It's not foolproof and doesn't need to be. It's role is to make sure respectful users know that you'd genuinely prefer they not steal your stuff (not everyone actually does care about that).