Whenever I do take my Gray outside, is only when I am out there with him and watching him. When I do, he goes right to anywhere where there is dirt and rolls and rolls in it! Why does he do this, does he think he's a pig, or something?
The way I see it is that they roll to cover up their own scent, so predators can't find them (or something like that). All my girls love rolling in dirt, the smelliest the better, but Molly's the one who really relishes it. She's also the one who tends to stink of poo the most, so my theory seems to fit with her, lol