I don't know why but I like to take a pouch full of pennys and use them on self service till machines. I may have £8 worth of pennys in a pouch and have shopping that costs £10, I would then use my card to finish the balance. The self service till machine is very patient, it doesn't mind if I have hundreds of pennys; I would be putting them in one at a time then I would press the pay by card tab to finish the balance with my bank card and would pay the £2. Most self service machines can take mixed payment but not all of them. I know which shops have the machines that take mixed payments and the ones that don't. I feel satisfied when I dump a heavy mass of coins into a self service machine.
Perhaps I can get a novelty coin pusher like the one they had in the arcades but smaller.
It is an Alan Thing.