I hang mine from holes in the riser, never the cam or limb. I have no idea if it would hurt the bow to hang by the cam or limb, but it can't do anything good. Kind of like carrying a bow around by the string...
I have been handing bows by the limb on tree limbs for about 20 years. Nice to keep it up off the ground away from critters. If there isnt tree close by bring it in my shelter and lay it on top of my pack for the night