I suspect that some dogs eat poo because it isn’t well digested and they know from the smell that they can get something out of it, some probably do it because they can use the extra digestive enzymes, and some do it because it is a disgusting habit that they like.
Grass is the same way, some like it, some need something out of it, and some need to vomit.
I had a dedicated poo eater and when I switched to a high protein food with good digestive enzymes, he completely quit, except when we babysit a friend’s dog that eats crap food. He no longer eats grass, since I started giving him a super green supplement. We haven’t had any vomitting issues, so I don’t know if he would still eat grass on an upset stomach.
