most of the cash costs are time counting it not moving it to the bank. Those seconds add up. There is also loss to crime since you will get managers stealing from the safe, and clerks form a till - both done in ways you cannot prove. And outright robbery.
Having been the manager at a place that handled a lot of cash, I spent several hours every shift counting all those tills. The clerks might only need a few minutes for their part, but then the till goes to a backroom where the manager counts it again. Then all that cash is combined into piles and counted again.
I've spent plenty of time counting cash and filling out bank deposits, but it was a volunteer position, so we did everything by hand. It's pretty error prone, but we only had to do it once if the cash matched the receipts, which it usually did.
Bill counting machines start at less than $100, and they make it super quick, so accuracy and handling time isn't really a problem any more.
Most retail theft is of inventory, not cash, and chargebacks will easily surpass lost cash anyway.
Having been the manager at a place that handled a lot of cash, I spent several hours every shift counting all those tills. The clerks might only need a few minutes for their part, but then the till goes to a backroom where the manager counts it again. Then all that cash is combined into piles and counted again.