Well, not everybody agrees with the benefits of the whole word method. While I believe that different methods work for different kids and no knowledge can hurt a child, a lot of people prefer the classical, the traditional teaching methods. Moreover, as I recently found out, even some governments prefer to set their strong preference for a particular method: whole word method is recently prohibited in France. While it makes me happy that we live in a free country (I do not believe US would ever let something as restrictive pass), where the government does not prohibit various learning strategies, there people who might support French government's decision.
Regardless of my own personal opinion, I believe every parent should make an informed decision on what's best for his/her children, taking into account not only various marketing campaigns or friend's preferences, but pros and cons of every system. So if you are considering a whole word method, you might be interested in some of the opposition that is build against it.