A Fine Line
Each country has their own rules about forming a line to receive a service. Some countries have a first-come-first-serve basis, and in other places, you have to push in to be served. However, in Sweden, you must respect the line culture.
It is common courtesy to form the back of a line and wait patiently to be served, without complaining. This is a form of mutual social respect in Sweden. There are some businesses who employ a ticketing system, however it is almost redundant giving the ubiquitous consensus to line.