At lower speeds would it be much different to a moving walkway? As for use cases these would be unlimited! I imagine 10km/ph is as fast as a taxi would average in a busy downtown
You can put your legs in a wider stance on a moving walkway. Furthermore, if the walkway happens to stutter, the rest of the walkway's speed isn't significantly different from the speed of the patch you're standing on.
On moving walkway, you can still walk so you speed is moving_walkway_speed + your_speed. Here it's just walkcar_speed.