Bad? Not particularly. Let us merely say it is cross-Atlantic badinage.
And on that note, the language is actually called English, this site is in the UK and therefore as a matter of courtesy if nothing else, one should not attempt to stomp all over local customs with ones own version of them. When and if I post to a site in the US, I shall happily spell the likes of color, medalist, or even heaven help me, aluminum as asked (if it ever comes up).
One word to surely make me cringe everytime, especially when it comes from the mouth of a newsreader, is "winningest".