So an additional cashier was called over to help get you out quickly and just because he was on his cell you are appalled?

Since he wasnt in uniform there is a good chance he wasnt even on the clock or working that day. He might have just jumped on the register to help out while he was there. Try to be a bit appreciative and not want him repremanded for helping.

While I agree people shouldnt be on their cell phones while doing business (employees or customers!!) I think you should be grateful he helped out.