Pirating makes sense when the pirates end up providing a superior product that the publisher won't provide at any price.

This was true for video games, where the copy protection schemes often resulted in a bad experience for paying customers.

But for an OS, having to enter a product key once doesn't seem to harm the experience as much as possibly getting a rooted kernel would.

I think, in general, there aren't a lot of good reasons for grown-ups to not pay for the commercial software they want to use.