There are plenty of big, dangerous wolves, but they generally help the hero. And if that happens to involve eating up the king and all his court, that's only when the hero of the tale has been ordered to bring all the wolves of the kingdom to court by the king who is looking for a pretext to kill him. (The only person in court to object to his cruelty, the princess, escapes the devouring.)
There is, of course, Little Red Riding Hood, but other than her, most big bad wolves are in fables, not fairy tales proper.
