* Almost every Costco I've been to, the food vending is a window on the outside of the building (so before the checkpoint).*

I've never seen a Costco with the food vending in a window on the outside of the building. I've always seen it against the wall after the checkout. Which is also after the checkpoint.

I think a window on the outside of the building only works in moderate climates. I don't see it working in Phoenix or Minneapolis.