Yes, unless they have permission. If the mesh original source is the work of someone else, it is piracy if they're releasing it to the public. Of course, if they've changed the mesh enough, it becomes hard to prove. I'd let Jim know and point him to the site. As the author, it's up to him to deal with it. Do they seem to be using the same textures? Sometimes we forget that the mesh isn't the only thing that is propriatory.