I think my physics teacher would have said "Your observations are correct, but they're not the answer". Or as Mr Scott would say, "Ye cannae change the laws of Physics, Captain."
The relationship is defined by the equation KE=1/2mv² and is quite incontrovertible.
What you're talking about is how the pellet loses velocity, and thus energy, as it travels away from the muzzle. There are multiple factors involved in this, such as initial velocity, pellet mass, shape, frontal area, air density etc, and is an area that provokes continual discussion in all aspects of shooting.