It’s unclear exactly how this is happening, but it appears that some gamers in the US are getting full access to Yakuza 6 after downloading the demo, complete with trophies and everything else. Coming in at 35.6gb, it’s not really a surprise that the demo contained the full game.
Unfortunately, this looks to be restricted to the US version of the demo, which was only available for a short amount of time before being pulled.
This isn’t the first time it has happened, but it’s been a while. It’s definitely never a good idea to include the full game in a demo.