Where am I going? To make room for people trying to clear the intersection behind me. Failing to pull forward means they’re either stuck on the far side for another cycle of the light or they’re going to block the intersection. With really busy intersections leaving those big gaps can make a huge impact on traffic trying to get through the one behind you.
In my area the biggest factor is multiple families purchasing homes together. When you’re splitting the mortgage it’s a lot more affordable.