If it's any consolation - I still screw it up.
I prefer to use the drive through because it's easier than dragging 2 or more kids into the bank with me. I can just leave them strapped in. I have this bad habit of, after I'm finished and I put the tube canister on the slot I either put it too far in (if it's the kind where you roll it into the tube in back) or pushing the button to suck it up through the tube. I'm sure more than one teller has gotten it, opened it and gone "What??!" before realizing I was driving away and had sent her an empty canister. Then depending on how quickly she sends it back the next person in line ends up with no canister to fill at the moment. Somewhat minor I'm sure.
If I'd been a customer there I would have wanted to tell the guy to get off your back for ya.
Fresnelly - this system is designed so that there can be multiple drive throughs side-by-side working at the same time without tellers being out 'in' each booth like toll booths. I have seen a couple banks with smaller booths outside the bank so they can have more than one drive through. This way they have access to the interior of the bank. It does puzzle me though when they have more than 2 drive throughs open when they only have 2 tellers working. Seems I'd get more confused as a teller getting more than one customer at once.
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"Always learn the rules so that you can break them properly." Dalai Lama
My Karma just ran over your Dogma.