They've had no more or less 'ground out' games than either of the big 2 IMO, even the narrow results they are usually the better team.
They don't have the players to play like Barca or Madrid anyway, since those 2 have 4 times the budget. Atletico's strengths are in the organisation, workrate and collectivity of the players. Even their main man isn't a superstar like Messi or Ronaldo, he's a scrapper who has the face of a man who's seen many crimes. Hopefully they get the job done, its far more of an underdog story than many will give credit for. Doubt the duopoly will be broken for another 20 years.