Rockstar said GTA 6 costs $79.99 across PlayStation 5 and Xbox Series X and S, confirming a $10 jump from the standard $70 we’ve seen this generation. The Ultimate Edition, meanwhile, is $20 more, priced $99.99.
GTA 6 physical copies do not include a disc, Rockstar has confirmed. They’re just a code in a box



I am pretty sure that you need an online connections to Rockstars Server to install/activate the installation. Never ever they will let you install/play the Game if you can’t connect to the servers. Otherwise you could, as you already said, duplicate the game. Rockstar will try to prevent this. So what’s the difference between have the Files on a disk, vs. Download it from their servers if they could just flick the switch at any time and prevent you from starting the game.
I didn’t say anything about game duplication. If Rockstar requires a phone home to play, then that is also shitty and don’t support that either. But I’m not aware of if they do or not.
It’s just a guess, but I think they’ll tie the installation to your account, or remove the game from your account if you lend the disc to someone else.
Well, there is no disc for GTA 6. Only digital codes.