Some people really hate to be reminded that their treats are made of animals. I like to remind them, because sometimes that leads to people changing their behavior. Also it's funny.

Soil muncher doesn't sound very cool and it doesn't roll off the tongue very well. Dirtmuncher just sounds superior. You could also go sexual style and call them "spermophages" for eating fruit but I'd advise against it as we wouldn't want your mother to think you're asking for her.

Since you also eat plants that doesn't really work lol