Not, mind you, battles on the page. Common soldiers tend to be either demobbed (see "Bearskin" or "The Twelve Dancing Princesses") or deserters ("The Blue Mountains" or "The Devil and his Grandmother"). But kings are always going out to war. Bog-standard way to separate them from their brides long enough for them to get false messages about how the queen gave birth to a dog instead of a baby, or for a witch to turn the queen into a duck.
BUT -- they don't tell why the king goes to war. It may imply that his kingdom's been attacked, but that only raises the question of why the other king did it. Especially because the wars can be tied up (with little bows on top) when they are no longer needed to separate the hero and heroines.
Ah, the need for a proper fairy tale reason.
Perhaps the foes aren't even human. There are a couple of malicious creatures that might be explicable as foes.