That is correct, the rich don't pay any taxes at all (whenever the can). The was a recent thread on HN regarding tax audits [0]. What I got from that is that the IRS cannot afford to audit the rich because their taxes are complicated and they don't have enough resources to do so. They choose to audit the poor instead because, it is simpler..
link [0]: https://news.ycombinator.com/item?id=21176705