I do not know why you expect this behavior. The "r" command replaces the selected characters by another character. In you example the first character typed is "C-r" so the result should be something like
^R Bar ^R Bar ^R Bar ^R Bar ^R Bar ^R Bar
If you have tried the scenario I provided, you would have noticed that the result is not as what you thought either.
and this is indeed the result in both, evil and Vim (at least in my Vim).
What you said is what is working in Vim, not what is working currently in Evil, however, I think what is working in Evil is even better and more useful. I hope you are not going to follow Vim this time, and I believe Evil has done better than Vim in this matter and I don't think we have to always blindly follow Vim even when we know it is not good in the specific situation. If you guy's decide not to follow Vim here, than making "C-r" work in this situation will be even better. York