Why do people instinctively line up when they are trying to get in somewhere or talk to someone?

Lining up to get in somewhere or to talk to someone is the most Nobel way to execute the task.

Explanation:

Standing in a line to wait for your turn is the best way for the standardization of society. This phenomenon has been in practice since ancient times from France.

The French people called it standing in a Queue for the prioritizing the person for the task. Nowadays in every public places it is used instinctively like in schools, in movie halls etc.