Lol, and CDP wonders why GOG isn't profitable anymore when they released garbage like this constantly.

I have actually heard of this game and some buzz surrounding it.
If i remember correctly it was made to make people think twice before eating meat or something.
the idea was if you played this game you get more empathy with the animals or something and as such woudnt eat as much burgers or meat. pluss a dose of humor tossed in.
But im not too sure if that woud have any effect.
I mean, there have been games where you can kill animals fo several years already.
theres even Hunting games

To be honest, me neither, but as you said, the game is here, the extras should be here too.
It's a matter of principle, even if in this case, asking for the artbook equals asking for punishment.

Here is an artwork of the game, for anyone curious :
https://cdn.akamai.steamstatic.com/steam/apps/1816590/ss_6cddb03a1cd83657b72caaf5c7bc2fcb7dd458b1.jpg?t=1638551437

Since then they denied having that stance, but this was news just a few years ago:
https://www.pcgamer.com/tinybuild-rebuts-story-that-it-doesnt-update-the-gog-versions-of-its-games/

The quote from a representative that got them into trouble was as thus:
"Updating games on GOG is very unlikely because games are continuously torrented through DRM-free builds," the rep said. "We appreciate people who purchase our games via any playform however we have to be smart in business and knowing that updated versions of games being stolen DRM free is not smart business."

It is telling that tinyBuild still after all these years did not learn anything, as already pointed out by Alexim.
I personally won't judge by that article or the claims about whatever their internal stance on DRM-free updates may be.
I'll wait and see whether they update their games and stop treating GOG customers as second-class - they can claim whatever they want.

What some publishers apparently don't get:
If you deprive the DRM-free build of important features or updates, I won't go to a DRM'ed store and buy it there, out of fear of missing out.
I will just stop buying from your company altogether, instead.
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Edited a few minutes later: months -> years, changed formatting

OK, but what is the gameplay? Do you cook burgers and you shoot horror creatures? Or something else?

You cook burgers and slowly try to discover the story and lore behind the game. There are secrets and collectables that expand on the story and world you live in as well as cook burgers.

Also, there seems to be a simple crafting system for some items, some exploration to find collectables and explore hidden and later opened areas that expand on the story.
You explore to find collectibles that explain the lore. You explore unlockable areas that also has a simple crafting system. With cooking burgers, there seem to be some boss fights as well.

Oh look, it's a cheap, low-budget FNAF rip-off....

Nice one GOG.... Another load of shovelware crap that only 3 people will buy.

It's in the same universe as other games from this indie developer.
Northbury Grove series you can get it for free: scythedevteam from itch.io

So Happy's Humble is a first full retail game basically. played 4hours already, its fine :)

No problem, you can also search up some gameplay if you would like.