I used to be very afraid of long single lines, until I studied a bit of queue theory in college. I now feel angry whenever I see lots of small lines, and relieved when I'm in a store that has a larger single line with a bunch of "servers" at the end.

Unfortunately that is the ONLY thing I got from that subject: "single line with lots of servers better than lots of lines with one server each". I can't really remember anything else, like WHY this is the case or how queues work. :/