Going on and off the..

Escalator in Prague's subway. What this has to do with ethics and freedom? Imagine that people are told to travel up the escalators while standing on the right side. The left side is used usually for those who walk the moving stairs up, although there is no information that the fact why the people need to stand on the right side. (and hold the trail) is because of the fact to have the left side free for the faster ones. What would happen if somebody would walk up the stairs on the left, stopped in the mid of the way up and just stand there. Is it ok unless somebody walks up?