And social rules have involved to minimise delays:
0. You place the groceries on the band "in the right order", ie heavy/solid goods first, light/fragile things last (so everything can just be shoved into the cart)
1. When your turn is coming up, you wait until the previous customer has removed their cart, and quickly put yours in place.
2. Next you help the cashier shoving the groceries into your cart, maybe arranging them a bit.
3. As the end of your purchases approaches, you prepare to pay (while the cashier is still scanning your last items), pull cash/card from the wallet, hand it over, and boom, take your cart away while the cashier starts scanning the next customer's items. (This works even faster if you are not alone.)
4. GOTO 1.
I miss Aldi.