There are two ways around this problem, though. The video type is stored in the file as an ATOM (metadata for QuickTime and MPEG4) called stik. You can use a hex editor to modify the ATOM directly, but this is very clunky and dangerous.
A better method is to use the open-source app Atomic Parsley to re-write the file with the stik atom set to TV Show. While you're at it, you can also set the TVNetwork, TVShowName, description, TVEpisode, TVEpisodeNum and TVSeasonNum atoms.
Please remember that Atomic Parsley is still beta, but I have been using it for a while and not lost any files or data. Have you backed up lately?

