Vampire (Dracula) Myths and TV

So the other night I was watching Buffy the Vampire Slayer re-runs. It just happens that I watched the episode where Dracula made an appearance. I find it interesting that, in the majority of the show's episodes, the vampire myths have pretty much been ignored, but once Dracula is brought in, the writers suddenly remembered all of the myths to go along with vampires.
                One of the things they remembered is the method of transportation for vampires. Dracula is shown to be using the method of travelling in his coffin full of dirt. The other two major vampire characters in Buffy, Angel and Spike, never use this method of travel. They prefer to drive everywhere. They might walk to some places, but they both have cars and both can drive.

                Another thing that comes to mind is that neither Angel nor Spike use any form of charming. They only use normal seduction techniques to get women to do what they want. Dracula, on the other hand, still uses his charm techniques to get women to do as he wants. Dracula is able to put Buffy and some other characters under his trance. Granted, Buffy is able to get out of the trance while the other characters put in the trance had to wait until Buffy defeated Dracula.
                One of the main myths that I am happy that the show kept true to is that there is only one person who is actually able to kill Dracula. That one person has to be a werewolf because they are Dracula’s sworn enemies. With this in mind, the writers had Buffy defeat Dracula in battle, but not defeat him permanent. They make a point of showing that Dracula was never truly defeated by Buffy.
                Another thing that comes up is that Dracula always has to have a castle. Is this supposed to be a reference of how Dracula is based on Vlad the Impaler, who was Prince of Wallachia — and not of Transylvania? I think that it is more than that, though. The majority of the vampire movies I have seen always have the vampire in a castle of some kind. Once again, there is a discrepancy with Buffy’s vampires, mainly Angel and Spike. Well actually, mainly just Spike. He lived in an underground hole under a mausoleum. Angel has an apartment. Once Angel got his own show, though, he got a hotel that resembled a castle.
 I understand that the show Buffy the Vampire Slayer, and the show Angel for that matter, want to show that they are modern shows, that they are not stuck in the past with what they may consider outdated myths when it comes to vampires. I can completely understand this thought process, but I find it incongruous that when they bring in an old vampire, aka Dracula, they decide to bring back those myths; kind of dust them off and pretend as if nothing is different from what they have been doing. This confused me — just because the vampire is newer doesn't mean that the myths can be dismissed.