Glad it is not just my imagination... I noticed that too.
Not sure how it improves the ride, but I see so many people do it, thought I would mention it.... when leaving, just stand on the moving walkway. Preferable side by side with a large group so nobody can move past you easily. With any luck the people behind you will be too meek to move past and then there is a huge backup and someone wanting to walk on the ya know, WALKWAY, will have to push past 30 people to get anywhere. It has to add to the enjoyment, otherwise why would so many people do it?