The Copy and Cigarettes blog just wrote about the different kinds of Chipotle customers

In short they are:

• The Experts - regulars who can order quickly in the right order.
• The Pointers - can’t communicate other than pointing (often over the sneezeguard) at their desired food
• The Question Askers - apparently don’t know how to read and instead want to ask about everything
• The Line Confusers - order their food in the wrong order, which screws up the whole process
• People With Kids - which is more of a general thing than a Chipotle thing
• Cell Phone Talkers - again, more annoying in general than specifically at Chipotle
• Order Takers - have taken orders for their coworkers or friends and slow down the whole system as a result

Check the full story for details.