archeology

Starvation probably.

The original wheat wasn't used for food, but as a household item.
Gather it, beat it, wash it, beat it again, pleat it and you get some tutorial grass armour in your sandbox survival game.
Mix it with dirt, dry it, then stack it together and you have the tutorial shabby dirt brick house. Can even use it as a grass roof.

Anyway, you have some leftovers, the kids take it and play house. The crushed grains mixed with water turn to paste, let it near the fire. Holy shit, that baked bread scent starts wafting over and you haven't eaten in days! You take a bite and it's fucking delicious!

New food recipe unlocked!

So yeah, I made all that up, but sounds plausible no?