Also don't need to have clocks at all, which was an industrial-age invention. The concept of standardized time and hour-long timezones dates from the mid-1800s, and was a construct of the railways (which needed to publish schedules that'd be valid across long distances). Before then each village or region had its own time.

https://www.thecanadianencyclopedia.ca/en/article/invention-...

Do you think agriculture hasn't moved into a post-industrial age? Modern farms are tightly integrated into a global supply chain from imputs to product and definitely need to work on the same standardized schedule as the rest of the world.

I still don't understand how the wall clock prevents them from getting up an hour earlier or later.