City of Steam: Arkadia
You'd be surprised at how much interaction the game needs for certain things, and how hard some content can be even if you've bought a lot of power.
Auction House / Market Place requires players to buy things with Electrum. (Similar to Neverwinter's Astral Diamonds. TERA's old subscription system, and WildStar's "C.R.E.D.D") Electrum is the cash shop currency. They recently added the ability to resize the windowed version of the micro-client, hence why my screenshots are a goofy size.