Yeah it's a waste of gold but I'd take a loss to have some genuine fun. Also have not completed a run yet the final bosses have been brutal especially if the treasures you select don't synergise well for the late game. Have tried to get a basic meta deck going but RNG of the treasures and loot crates kills it.Enjoying the Dungeon Runs too. Haven’t finished any yet. Have got up to the last boss a couple of times but got slapped. The deck build really doesn’t seem to matter greatly until that last couple of fights.
Bit disheartening getting 7/8 with nothing to show for it though. Wish it was somewhat better integrated with the rewards system. Some dust or a small amount of gold would be nice, or at least let it count towards your daily quests.