> The paradox of tolerance states that if a society's practice of tolerance is inclusive of the intolerant, intolerance will ultimately dominate, eliminating the tolerant and the practice of tolerance with them. Karl Popper described it as the seemingly self-contradictory idea that, in order to maintain a tolerant society, the society must retain the right to be intolerant of intolerance.

To answer your question more succinctly, because the poster isn't the only person who will read these comments.