[ryusage]

The most interesting fact about the self-checkout systems, in my mind, is that they actually have no designated area or instructions for how lines should form. People just intuitively wait outside the general self-checkout area, and use the machines as they become available. So, at least in some circumstances, the single queue system obviously can make a lot of sense to people.

[nlawalker]

This is the interesting part to me as well, although I do have a couple of anecdotes:

- I have seen at least one store where a single sign is placed at the front of the full collection of scanners stating "line forms here" or something similar, regardless of how many there are or how they are arranged. - I have seen at least one case where, in a store that did not have the above sign, one line formed for each "vertical" bank of scanners. For example, in my local Safeway, there are six scanners: two rows of three each, lined up next to each other, parallel to the checkstands. It is pretty intuitive/obvious that they don't intend for people to line up at each individual unit in a single row, but often a queue will form for each row.