I know what site I'm on, but I have to ask...

[Lace Neil Singer]

Someone tried the old change-up scam at my local cafe the other week; the server was far too sharp to get caught & brilliantly dismantled the attempted scammer's shenanigans.

That happened once during the Christmas season, when we had a temp working at the petrol station. Said temp, let's call him Justin. He was working thru his uni holidays; he was currently doing a maths degree. The scammer tried to confuse him by asking for his change in different ways; each time, Justin counted out the change correctly. Eventually, the scammer just gave up.