Is "grubby" different from "polluted"? Is "paw" different from "leg"?
"Grubby" holds a negative connotation, meaning "dirty" or "grimy." The full expression is "grubby hands" or "grubby paws," which is used when someone is touching something that doesn't belong to them, or when someone is getting involved in a situation that does not involve them. Thus, we can understand the speaker (Mike) as saying that Sulley's hand was in his bed, and that it did not belong there. "Grubby paws/hands" is usually used to refer to people. There is no similarity in usage with the word "polluted." Also, "paw" in the literal sense refers to animals only and not people. Ex: Get your grubby hands away from my pizza! (Keep your greedy hands away from my pizza!) Ex: Keep your grubby paws to yourself. (Keep your hands to yourself.)