Lazy writing on the journalist’s part; “Known as the Pagoda because of its removable hardtop,”, of course he should have written that it was the shape of the hardtop that gives the car its name.
One can't always blame the writer. Sometimes it's the editor. When faced with fitting a submission into so many column inches, editors must find a way to shorten the content without fundamentally altering the essence of the story. An adjective here, a descriptive element there, rewording a phrase for brevity and pretty soon it fits!