The milkshake machines were in the back. Those were the days when you added the syrup to the semi-frozen slurry and had to mix it. I think today, it comes pre-flavored.
I think there were a lot of customers that didn’t know they were used.
I've never worked in one, I just know what I've seen. Pour stuff in a machine push the button open the tap fill cups.
The local dairy as a storefront, and there they make milkshakes.