Well, the game relies on the reach of the buildings, the Arcane card "Increaser" helps with that (you can hold Shift and point to a building to know its reach, so how far away the ingredients it will use can be).
There is no other way in this demo to increase building's reach, so if your wheat crops are too far away, a solution could be putting a mill a couple of lands away with some Increaser to boost its reach and the Bakery the same, between the Mill and the Gourmet Kitchen, with Increaser you can reach the other side of the map this way with ingredients that pass through several buildings.
We found this limitation of distance an interesting feature; hope you like our idea behind it, and thanks for playing!