You probably keep a lot of cash at once!
When you are connected to Facebook, the Cash King is first determined as a friend of yours who has over a certain amount of cash. If you don't have any friends with that amount, a random player will be selected.
It is entirely possible to be someone's Cash King a few times in a row for 2 reasons:
- You keep a lot of cash and even after being stolen from once, you've still got a large amount
- That friend doesn't have so many Facebook friends playing and so the selection pool is smaller and you're more likely to be the Cash King