I agree with this sentiment a lot. I only make the exception here for this game specifically because:

- He has already bought the product

- It works offline and you don't need to ever update

- The game is fun as hell and there's really nothing like it

If this was the case with some other piece of software such as Windows (which funnily enough is also by Microsoft) where I do have alternatives, instead of pirating I just use Linux/Mac/BSD/whatever_else instead. I should note my personal experience with the game has been very pleasant specifically because I choose to play it "pirated"/"offline" even though I've purchased a copy of the game a long time ago, it's just more convenient, safer, and more private. If MineTest or something else ever gets to a state where it's as polished and fun as Minecraft 1.0.0 I'll certainly migrate.