I've got a guildy with a completely full materials storage. All legit.
Early day Tombs players made TONS selling sigils and other rare skins. My guild leader dropped a r8 15^50 crystalline in fall 05.
I had a friend who was in the first guild to own cavalon. Farmed zodiac stuff and made millions.
When Zaishen keys were 5k, there were GvGers with 2000 reward points. Which is 2 million gold.