As Phil implied, perhaps the character of Vicki in the film is actually a composite of both Vicki and Maggie from TOS. That would explain the scenes of Vicki in the assylum.
Someone else (Micheal?) mentioned the coffin in what appears to be a bedroom Perhaps more evidence that the family (in the film) is aware of Barnabas being a vampire and allows him to take refuge in the mansion. That is a "take" that will be hard to swallow for me.
As others have said, this doesn't seem to be a comedy. I was trying to find words to describe the style of the production, and really came up empty. Would you call it -- traditional? exaggerated? fantasy? Creepy? I certainly would not call it realistic. Exaggerated gothic. How's that?