After watching the gauntlet a little I am surprised how many of the receivers let the ball come all the way to their body or just look plain awkward catching the ball. There were some guys who looked really good though and catch the ball with their hands. Vernon, Woods, Wilson and Wheaton all look like actual receivers and not just big and fast athletes.
What are scouts looking for in this drill? Do they really care that much if you catch the ball or more that you look like a natural pass catcher?
It's designed to evaluate hand-eye coordination. There's no real practical application for it. But yes, they are looking for the natural hands catchers.
Most of them have probably never done a drill like that, they are used to just catching a single pass, securing it and moving upfield.