...they are in the drive up line. That's why you got in and out on a reasonable time. If they all went inside, that line would not have allowed you to get your coffee and out so soon.

 I'm not a regular at any food joint, but I do know that the most local to me mdonalds caters to the drivethrough priority. I think this is because of the 2 sawmills in town and the large amount of "regular" traffic they have. The regulars want the drive through and the highway passers by usually want to get out a and stretch for a minute anyway. Many have a large trailer behind them. In fact the mdonalds has I think 5 truck parking spots and a side road with more truck parking.