It's simply some kind of easing function, and if the universe does have a designer, it's obvious to see that said designer prefers smooth transition and curves

It's simply some kind of easing function, and if the universe does have a designer, it's obvious to see that said designer prefers smooth transition and curves for most macroscopic phenomenon. Also by defining the inverse square law you can maintain a cohesive interaction model between different objects and regions. Their sphere of influence (which can be described by gravity waves) will now just be superimposed on top of each other without extra work. Or even crazier, maybe it's a combination of both, maybe there is a hard cutoff after all once you pass the event horizon.