The profit is in raw materials

If you want to make WoW Gold then you have to deal in raw materials.

To gain skill in professions you have to turn raw materials into something. Ore is smelted into bars then crafted into, well, something. WoW players like to level their skills no matter what they are. The modern economy of WoW has many level 80 players funding their "alts" with the mountains of gold the level 80's can make. Spending a few gold to level up skills on a new character is much easier than doing the gathering themselves.

That's good for us. The high demand for those raw materials means the lowest priced items in the auction house sell quickly. We can take our profits and invest it in more trades or buy that sweet weapon we've had our eye on.