Let the two balls roll down the slope!
The slope at the start of the routes (the gravity) gives speed to the balls. They roll together moving in an almost straight direction, in a steady tempo until they reach the "hole".
It is true that one of the balls has to pass a shorter way, but in the case of the other, longer way thanks to the hole is abundantly compensated by significantly greater speed.
Freefall is frequently mentioned as an example of uniform acceleration. It is a widespread disbelief that heavier objects fall with greater speed than lighter ones. Objects fall with uniform acceleration regardless to their weight.
The velocity of falling objects is diminished by different factors intensifying drag (fluid resistance).
