Head to the bus station before the morning rush. The pastries are fresh and cost half of what hotels charge. I found a spot in Madrid that makes churros way better than any buffet. Ask locals which bakery they use, they always know the best ones. You save cash and get a real taste of the place. It turned my whole trip around last year.
Hotel breakfasts are basically paying for the same sad croissant you could get anywhere. Bus station bakeries have way more character and better coffee, in my experience. You're basically paying extra for the privilege of eating in a carpeted room.