Pure urban, man. Folks here claim the aisle seat first. They do not like to crawl over each other to get in or out of the window seat. Often, the aisles will be full of standees, even though there are empty window seats. It seems to me that a sociologist could get several learned papers from this behavior.
Life is too important to clutter it up with rules.
There are only situations, and each will be unique, with it's own imperatives. Which brings us back to the introduction. When you can, whether the light is green, red or nonexistent.