You must live in a civilized land. What you describe is how things should work, but in practice it's not that way in many countries. I've driven in many count

You must live in a civilized land. What you describe is how things should work, but in practice it's not that way in many countries. I've driven in many countries, and what you describe has only been common (in my experience) in Netherlands. But even there, it doesn't always work. Parallel street parking is very common. The car wanting to reverse into a parallel spot will pull past it, put on the hazard lights, and then back in. Usually cars behind, if they are not already following too closely (which does happen a lot), will stop short to give you space to back in. But even in NL, this is less common in a parking lot that is nearly full. People are circling, desperate for a place to park (since the nearest next alternative could be a long way away), and will absent-mindedly or intentionally swoop into a spot that you just passed by.