This is just a cheap replacement of a sprite. Anyone could do this, but if someone is lasy they COULD use this. I can't say it's bad since it's just a sprite replacement
I wouldn't call it cheap. Sure, he could have done something more creative, but I wouldn't call it cheap at all. It all depends on how someone used this in an episode. It would be boring if it just sat there and you attacked it, but there are plenty of ways to spice up boss fights.
Actually, as Socknic said, it's more than just a sprite replacement. You could attach it to a Lakitu and make a proper authentic Big Boo battle like in SMW.