I recently fostered and then adopted a sociable, young male who kicks dirt over his poo. Or rather, he does some rear foot action kicking back in a way that I suppose could do that, but mostly looks like a victory dance. A few months later, my youngest female started the behavior -- she's 2 years old (not a pup, but still impressionable). It appears to be a socially learned behavior--she never did it until she saw him do it (she likes him, so she's emulating a dog she thinks is "cool").
As for your other observation, the only male I had who only lifted his leg on one side but not the other ended up having HD--we eventually figured out that he avoided lifting on his "bad" side. My other males lift on both sides. If you have one that only lifts on one side, you might want to check the hips with an x-ray, just to be sure they are both okay.
Last edited by Magwart; 05-09-2014 at 08:46 PM.