If you knew the game was bad you wouldn’t buy it. That equals no sale for the publisher.

If you pirate it, don’t like the game and delete it. It’s the same result.

If you pirate it, like it. Then buy it, then everybody’s happy.

See, they don’t care if you like the game or not, so why should you care if it’s ethical to try a game? Especially if you buy it in case you like it.