In RuneScape, some skills have benefits for exceeding the minimum level to obtain something. You will mine iron rocks at a faster rate at level 80 mining versus level 50. Likewise, at level 99 mining, you will obtain runite ore faster than at 85. It is important when harvesting high value resources if you are aiming to make a profit.

I haven't found any game economy that even comes close to runescapes

Have you honestly invested time into any MMO besides RuneScape and apparently MapleStory? RuneScape has honestly one of the worst economies and trading/interaction system in any MMO I have played. For the first 7 years of the game, there was no real centralized trading system until we got the Grand Exchange. Fally park and Varrock were the locations players set-up shop to serve as in-game places when not wanting to deal with the forums. When free trading was removed, the economy was flooded with junk that would have normally never been traded. People abused the system through price manipulation and still do in both games. All it takes is about 10b of wealth, whether controlled by one person or not, to manipulate the price of virtually any item in either games' exchange. There are some people who know the market, keep an eye on future updates, and profit of course, but those people made change compared to what merch clan leaders made. The economy never really recovered from the path which was set before the GE even was added in.

I haven't checked in on the economy in WoW in awhile. I stopped playing early on into Warlords due to the garrison system. If I wanted to play an RTS, I would have played Starcraft. They have over-complicated the game with the garrison system. A quick glance on my main realm showed a massive amount of gathered materials in the auction house and my old guild say the economy isn't doing too great. The great thing about WoW is each realm has a different economy influenced by the population. In RuneScape, everything is over-connected, which can be a good thing, but isn't in this case.