Yea I think that is a thing where the game screwed up a bit, there is no real use for money.

And in the first dungeon you can find all those expensive axes and sell them to buy the best armor available already... Good things should have been harder to get.

It should be like this:

You walk in a shop and you see this cool armor you want, but alas you only have half the money it costs and then you go and earn the money and it's so much more fun when you can finally afford it