You said this:
I mean...the whole industry is based upon the idea that losing weight and keeping it off is incredibly hard. But the truth is, that losing weight is as simple as eating less and moving around more. Keeping it off is as simple as teaching yourself what made you fat in the first place, and practicing not doing those things until they become habit.


Another aspect of weight loss that most people don't understand is that if combining a little bit of weights with cardio an individual can actually eat more (of healthier foods of course) as the body will need the additional protein and calories to rebuild muscle loss.
Weight training also helps a lot of people with appetite suppression. Some get appetite stimulation as well but the irony is that as I said before the body needs the calories anyway for muscle rebuilding. This caloric needs also helps buffer the effect of calories gained from the occasional "free day" or the slip up in the eating style better than just cardio alone.
I am a firm believer that more people need to integrate weight training (even body weight exercises are great!)