My guess, because they haven't been remastered yet and prepared for future HD syndication. These titles are high enough on the valued product list to get the best treatment but not high enough to prioritize the remastering ahead of other items. They don't see a need to release without remastering, and they've taken flack when they did for various seasons. Californians, on the other hand, most likely used existing masters, so it was just a matter of authoring to disk.