I don't know, that Stardew Valley game looks pretty painful too. I've got to at least be able to kill a wood elf or run over a hooker for it to be a video game. I saw in the comments of some youtube video people arguing about the differences in Farm Simulator games.....apparently people really do play it. I'd spend 5 dollars on it, but not 40.
I'm also in the same boat in wondering why people enjoy those farming games. However, I do remember enjoying Harvest Moon 64 back in the day. New farming similuator games though baffle me. At least in Harvest Moon you had to go around and plant and collect produce yourself. Why would I want to drive a slow moving tractor through crops for half an hour?
I tried it for a few minutes to test the 360 when I first got it. I couldnt figure out how to hitch the trailer to the tractor so I just tried to do sick jumps instead. I got like 3 feet of air. It was pretty fucking cool.