They just want to see Dracula rip peoples' throats out and transform into wolves or whatever. Seeing Dracula being first introduced as a friendly if eccentric old man then having the facade slowly fade away until it becomes clear that he's a monster holding Johnathan Harker prisoner is amazing and something a lot of adaptations don't want to do.
Related to that, by following Dracula Daily, I'm learning that the problem with most adaptations of Dracula is that they're way too eager to get to the supernatural parts of the story and so they skip all the psychological horror elements that actually make Dracula terrifying and intimidating.
