Well, if we go with furry=anthro then it's obvious, but if we go by furry= anthro with fur then it comes the question, does that green sponge part can be said to be an artificial kind of fur? (probably not), can eyelashes be considered fur?
That means another thing, if anthro means human-like, and humans could be said to have fur depending on who you talk; could humans be categorized as furries?
could an ape-dog hybrid be considered a furry, as apes are in some quantity human-like?
At the end of the day, it's just a thing about limits and where do people put them, some may see 20°C as hot, others see it as cold. Some words have different meanings for different people, sometimes the same person have 3 meanings for the same word.

Sandy Cheeks is a furry, no question.