If you have a full cart, you scan all the items, checkout, walk to the end of the belt, and bag all of your items.

Okay? But there's no cost savings on my end and I don't have all the codes memorized, so it takes longer than if a dedicated employee handled it.

with zero human operated checkouts running you get no choice

The humans are still there, though. They're hovering over your shoulder to make you did the job right and you're not buying booze under-aged and you didn't steal anything. All the business has done is off-load the manual labor onto the customer and slowed down the checkout process as a result.