They are not a joke, they are examples. Obviously they are not true life examples and as many people have pointed out there are many different factors that go into figuring out what an effective tax rate is. I was trying to assist the OP with the basic idea without them having to do searching and digging through the propaganda.
Here is the pro-fair tax http://www.fairtax.org/site/PageServer
Here is the anit-fair tax http://www.forbes.com/sites/timworstall/2012/08/22/why-the-fair-tax-will-fail/ That is just one of the articles, someone wants the details find it out for themselves.
I posted a similar example in another thread when someone asked why the Fair Tax is opposed, and I too caught hell for it. It's amazing the flak you catch for simply presenting another perspective (even if you personally don't agree with it).