These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Downer Ending: The ending may seem bittersweet at first, because even though there was no definite resolution to the truth of either of the four stories, the woodcutter still seems to altruistically take a baby home to live with his family. However, there are a couple of things to consider. One is that a third person stole the baby's blanket earlier, saying that in these times, one needs to look out one's self. Second is the look on the woodcutters' face as he walks away. He doesn't seem happy to be taking the baby; he looks almost horrified. It's possible that he's just going to abandon the baby and take whatever's left on it once he's out of sight of the priest, with the words of the third person weighing on mind. This would make the message of the movie be that everyone's a lying a-hole that's only in it for themselves, and you can't expect anyone to tell the truth or act honorably.
We are meant to think the woodcutter is lying about his story because he stole the dagger. But if what he says about having six other children to feed aside from the abandoned infant is true, he could easily be interpreted as stealing the costly dagger to make ends meet. And all the other aspects of the story could very well be true.