Seems to me its pretty hit or miss: you are either a crafter who became filthy rich, or you just don't care about the money and live on a use-and-spend basis.
I don't spend anything either. I offer more than I should for repairs, but that usually gets them done faster so I don't have to sit around town for hours on end hoping someone will repair my stuff for nothing. I won't buy the "latest gear" for my level, because I can't see spending 200k for an item that: A) makes a marginal difference performance wise, and B) will be ultra-mass produced within the next month.
Crafters are filthy rich because people have to have it now now now. "Hey look I got the newest thing! Never mind the fact I paid 600k for a shirt that cost the crafter 60k and 15 minutes to make."
There are fisherman progressing just fine at level 30+ with starter gear and maybe a willow rod. As a conjurer I can party up on tough mobs, or solo weaker ones with my "gimpy gear" for the same or more SP, not to mention kill faster and get more drops. Jellyfish being a perfect example, cnidae and umbrellas being a fantastic set of recipes for the low 20's alchemist.
I digress, my point is, gil is pretty meaningless so far. My daily leves pay for my repairs and even any random materials I need to buy from a NPC.