Timmy,
What you may not realise is that there have been shall we say, less than professional operators for as long as there has been carpet cleaning. You don't need to tell the public about them, they already know, many having experienced them first hand. And they don't have to be the bait and switch outfits either, god knows there seem to be plenty supposed carpet cleaners around doing an awful job as well.
Putting negatives in front of people in the hope of producing a positive and making yourself look good isn't the best of ploys IMO.
Simon