Ah yes, I've had all of the above, plus:
The passenger-seat order taker. The microphone on the rig at the place I worked was low to the ground, so the driver's door would block the sound waves if someone other than the driver side person tried to give the order. If I said I couldn't hear them clearly, they wouldn't move or have the driver say it... they'd just YELL REALLY LOUD, which I'm sure the driver appreciated.
The Stoners. Hard to make out over the chuckling in the car. Very slow to decide. Worst of all, there's that cloud that hits you like a donkey punch when they roll their car window back down at the window, because they've been hotboxing and couldn't wait to do it again after giving in their order.
The Cat People. Like felines in cartoons, some people are just scared to death of water coming into contact with their body... on rainy days they try to order with their window rolled up... or just open a TIIIIINY crack. Again, our microphone was set low. Guess what muffled the sound really well?