If you had a basket before you got to checkout, don’t dispose of it at the end of the line, BECAUSE YOU OBVIOUSLY WILL NEED IT WHEN WALKING OUT YOU DUMB MOTHERFUCKER! Stop wasting my time trying to juggle 10 items without a basket YOU FUCKING MORON!
What if I didn't get a basket before I got to checkout, but I barely juggled my 10 items successfully and then once it's all scanned I can't figure out how to juggle them again?
Usually people visit shops by car, without a backpack – at least where I live.
Putting stuff in your backpack may require some more careful planning than just throwing it back into the basket temporarily, before you pack your backpack for real at the packing table. People do do that, blocking the end of the checkout. If the cashier doesn’t wait, you need to be careful not to have your items mixed up with the previous customer’s.
Well maybe I am a genius then, because putting the hard stuff at the bottom of the bag and the soft stuff at the top is childsplay. Then if something's too fragile for a rucksack and you have got there by car, you can just handball it. Easy peasy.