Some of the best experiments involve psychologists casting off their lab coats, rolling up their sleeves and delving into the messy midst of the real world. Stanley Milgram (of obediency experiment fame) and his colleagues did just that back in the 1980s when they pushed in line at 129 queues at train stations, betting shops and other venues in New York. They uncovered interesting behavioural patterns, such as that people were far more likely to react to a line pusher right in front of them than one who pushed in several places ahead (even though the effect of the pusher on waiting time would be the same in each case).
Inspired by studies like this, Marie Helweg-Larsen and Barbara LoMonaco did the next best thing after actually pushing into queues. They surveyed groups of U2 fans queuing overnight to get the best positions possible in the general admission area at a U2 stadium concert.
An initial survey of 238 fans at a Philadelphia concert asked queuers how they would react to a series of line-pushing scenarios. Fans said they would react more negatively if an apparent stranger pushed in, as opposed to a "friend" taking up a place "saved" for them by others. However, fans didn't say they would react any less negatively if someone pushed in behind them as opposed to pushing in front of them (even though the former case wouldn't affect them directly). It also didn't make any difference to fans' reactions if they were currently nearer the front of the line as opposed to being nearer the back.
A second survey of 206 fans in Atlanta Georgia replicated a finding from the first survey: hardcore fans said they would react more severely to line-pushers than did casual fans. All fans said they would be more upset by a line pusher if they had been waiting longer. However, once again, fans said it didn't matter whether a line pusher barged in behind or in front of them in the queue - they'd be equally upset.
"Clearly people care about the context and situation of norm violations, not just about the objective set back associated with someone intruding in line," the researchers said. However, they added that this "moral outrage" response was probably related to more functional concerns. After all, "For U2 fans, any threat to the established queue might create chaos to the entire system and, therefore, ultimately threaten one's own position..."
Marie Helweg-Larsen, Barbara L. LoMonaco (2008). Queuing Among U2 Fans: Reactions to Social Norm Violations. Journal of Applied Social Psychology, 38 (9), 2378-2393 DOI: 10.1111/j.1559-1816.2008.00396.x