Nobody every told me that I had to be an interpreter to be a bank teller, and I am not talking about speaking a foreign language.  Consider the following questions from customers:

“Can I have a scribbler?” this was a accompanied by a circular hand gesture.
Interpretation: “Can I have a pen to sign the back of my check?”

“Can I have a thing to go?”
Interpretation: “Could I have a drive-up envelope for my cash?”

Also, some customers ask the some interesting questions, like the following:

Customer: What is the balance in my checking account.

Myself: You are currently overdrawn and you have a negative balance of $XXX.

Customer: How did that happen?????

My responses (To myself- “because you spent more than you had in your account… duh…”)
To the customer: “Well, let’s see, it looks like you had a check for $XXX that came through and made you overdrawn.”

And my favorite so far:

Someone came in that I am acquainted with. I said “hi” and got the response “You work here?”
  “Yes” I answered, “I work here in the summer”.  ( Last I checked they didn’t allow non-employees to stand on behind the counter and wait on customers… )

I do my best to be polite and respectful in my interactions with customers and their comments, and I don’t make fun of them while I am waiting on them. But I will admit that some of their comments are remembered, smiled about later, and sometimes shared.