Mark,
Actually, not quite true. If you go to the website of the Classic Car Club of America (CCCA) they do explain what they mean by "Classic Car" (and they always capitalize the two words). CCCA was formed about 1950, for the preservation, restoration and enjoyment of the great, grand luxury cars of the era 1925-1940, which is pretty much the era of the handmade, custom-bodied superluxury cars in the US (stuff like Packards, Pierce Arrow, Cadillac, Duesenberg, etc.). At the beginnings, they were quite picky about what they would admit to their registry as a "Classic"--back then, with the exception of a very few marques, the car had to be an open body (roadster, phaeton, cabriolet--fancy term for a convertible--from the above mentioned time period. As they went along, CCCA entertained applications for admission to Classic Status by owners of cars who felt their's deserved this sort of recognition--finally coming to encompass every body style made by most of the luxury car makers, with that recognition coming only by majority vote of both their board of directors, and the membership--sometimes, a lot of politicking went on. Over the years, also, CCCA has de-listed a number of cars, simply because there weren't any at various times listed on the membership rolls, and it was felt that perhaps their recognition had been not in the best interest of maintaining the standard they wanted to portray. Today, however, a CCCA-recognized Classic Car is something pretty special--go to Auburn IN over Labor Day weekend, see what some of these cars bring at auction.
As for the CCCA being at issue with the use of the word "classic" to define any car at all, they freely admit they cannot be any sort of arbiter out there in the old-car hobby, as the club has no trademark or copyright on the term "classic car", or even the descriptive word "classic". They also publicly acknowledge that within any given marque, there are cars that are truly the "classics" of that marque (Classic 55-57 Chevy, Classic Mustang come to mind here). However, they can, and do, restrict the recognition, within their club ranks, to just those cars which meet their criteria, that's all. In this, CCCA's definition is recognized, and used by most all other antique car clubs and organizations, even World-wide. But, you won't be in any trouble if you have a Gremlin, a Pacer, a Chevette, even a Yugo, and want to call it a classic--it's just that CCCA won't, nothing more, nothing less!
See ya at Fest!
Art