Why do people behave irrationally when queue

Observations over the behavior of people in supermarkets helped the scientists to clarify why people start to behave irrationally and bustle between queues, slowing their movement, and their own movement, said in a magazine article SSRN.
"Fuss between queues, the constant moving from one to another is absolute madness, but due to only one reason - people do not like to be last. Moreover, as the people are behind you, it does not matter how fast will move you. This feature, however, affect the human psyche as a rule, but one is 20% more satisfied with the place from last in the queue, "says Ryan Byuel from Harvard University.
In recent years, psychologists and many other scholars began actively interested in human behavior in everyday situations and unifying - for example in the choice of goods or when queuing at cash shop, and in traffic jams. These observations revealed several interesting and unexpected things.