I see you are not from the U.S. Perhaps your experiences in fast food restaurants are different than ours. There was a great thread that was titled something like,
"Oh no... You couldn't be that stupid!" but the search didn't bring it up. Maybe someone else has it bookmarked.

It was like 15 pages.
It was a
hilarious thread full of TRUE stories where
so many of us have experienced times at McDonalds drive thrus where you order: 3 cheeseburgers, 2 large fries, 2 shakes, one McNuggets. What you get is: 2
hamburgers, 2
small fries, 2 large Cokes, one McNuggets with only 4 nuggets instead because they couldn't count to 6.
Here is a similar thread:
http://www.disboards.com/showthread.php?t=669674
Well, then my remark doesn't apply to
them. . . does it?