I have seen it done many times in the field and have told them that it's not a good practice if they want to keep both feet. Another one that can be dangerous and get a foot shot off is cradling a gun with the muzzle down toward your feet while wearing a knife or some other accessory on the same side. Watched a guy return his gun to safety cradle it, start walking. He was wearing a knife the same side, the gun got between the knife and his body pressing the safety to fire. Repositioning the gun as he walked the knife butt got into the trigger and fired right beside his left foot. If one step later he would be missing his right foot.