That would be a horrible experience: You sign up (even if it’s just for a dollar) and then you would have to wait a month until you can play the new stuff. This way they are still giving away the single player campaign and one month of multiplayer for a fraction of the original price. If you want to buy the game it might even be cheaper to sign up and buy it with the included discount and then cancel again.
I’m pretty sure pentagons are a subspecies of bestagons…