I would say pretty norma, both of my yorkies did it. I had to come up with some pretty unconventional ways to discourage it. The cat poop has bits of cat litter and you definitely don't them want them ingesting that stuff every day.
In addition to eating cat poop, one of my yorkies even licked up cat vomit when my cat threw up her hairballs....ewwwwww. And then has the nerve to want to give lick on my face.
These little stinkers will eat almost anything.