It has no use to list cars which aren't cars. Even the "made for movie" has no real interest except those with a name on which we can do a search (e.g. batmobile).
A dedicated page for a Lotus Seven for example will make it appear in the Lotus Seven gallery, which may interest people searching for Lotus Seven in movies... but will someone search for "made for movie" in movies?
At least the "made for movie" and "custom made" from real movies are real vehicles, as they usually are running or at least looking like real vehicles with actors going in these.