I'm not sure why they don't follow the prompts though, terminals are set up in a way to give the merchant the least liability properly. You'd think the managers atleast would just say, "Do what the machine tells you".

I was in a Wendy's with a colleague and we had to show the cashier how to process it but he was quite happy to go along with what the machine asked him to do and we both completed our chip and pin transaction sucessfully.