This has always been an issue. I agree that Starwood hotels didn't tend to overly abuse the definition of a standard room, but I certainly ran across instances where they did. I agree it was primarily oriented to room "types" as opposed to bed "types" but I'm sure it occurred with bed types. (Room type frequently being oriented to "views" or something equally irrelevant).

I believe it could be solved by having a requirement that a hotel ensure that at least 20% rooms (or some number like that) are considered "standard rooms" to avoid more egregious instances of cheating. But I doubt that would ever happen...