My wife went out for pizza last week and came back with an incredible story. She ordered two pizzas on-line and went to the store to pick them up. When she arrived at the pizza store their computer was down. When she paid with cash, she was surprised to see the cashier pull out a calculator that she used to calculate the change due from my wife's purchase. The cashier explained that they had to use a calculator to figure out how much change to give a customer and that they would get fired if they were caught making change without the use of the calculator.
I'd guess that the pizza store didn't just make the use of calculators mandatory for no reason. They almost certainly did this because their employees couldn't do it accurately without a calculator.
It's somewhat popular these days to criticize the exit exam that California high school students have to pass to graduate. Opponents like to say that it forces teachers to teach just the material that's covered on the test, and that this reduces the overall quality of education. Supporters of the exam maintain that it's just testing basic skills and that its requirements are quite reasonable. If pizza stores have to require their employees to use calculators to make change accurately, I'd guess that the exit exam isn't testing enough.
The fact that people can pass the exit exam and still can't make change accurately may account for the following joke:
Question: What is 2+2?
Answer: A question on the California high-school exit exam