Because, as Kant wrote, "Examples are the go-cart of the intellect". If the examples don't work, then there is probably something wrong with the view they are examples of. The general point is this: it doesn't follow that because the differences between X and Y are undetectable, that there is no difference between X and Y. Don't you agree?
Of course I would agree, but I have explicitly stated why a distinguishable difference is important, because this is all meant to occur at a first-person level, and if an individual is trying to be justified that what he thinks is X is not actually Y, then there'd better be a distinguishable difference. The same applies in broad terms to different views on reality, because we are all "first-person" viewers. If there is a distinguishable difference between two views of reality, then one has to justify if view X or view Y is the non-fake view.
If you'd like to be more constructive, try to think of another example that does succeed, like me thinking up playdough, that way you can ask the other person if that's what they meant. It's much more constructive then coming up with another example that you think proves them wrong, like genuine and counterfeit money.