The reason I say, "Carbon Footprint = Pathetic Scam" sometimes puts those who are concerned with the environment on the defensive. They see it as a personal attack, or at least an attack on their causes.
I see "Carbon Footprint" as nothing more than an exuse. As long as a person boasts a "neutral" carbon footprint, they act like they are actually accomplishing something.
The concept reminds me of a good concept called "low impact camping". Low impact camping means that you do all you can to leave the campsite the way you found it (or better than you found it). A low impact camper will pack out everything they packed in. They will clean the coals, partially burnt wood, and other debris out of the fire pit. They don't cut down trees, dig holes without refilling them, or clear the ground cover from a spot without cover it up again.
If low impact campers followed the "carbon footprint" model, they wouldn't care what they did with the campsite, as long as they "made up for it" other ways. If they biked or hiked in, they wouldn't feel quilty for leaving food behind because "hey, we didn't pollute on the way here, and besides the animals can eat that food we left." They would feel justified in leaving a hole they dug, as long as they covered it with leaves to prevent erosion.
For anyone who cares about the environment, "carbon neutral" should be a joke.
The ONLY thing that helps the environment is Reducing our impact on it. If you decide to walk when you can, that is awesome! But what good did you do the environment if all it means to you is, now it's ok for you to continue doing something destructive?
If you're "carbon footprint" is "zero", but you are burning 20 gallons of gasoline more than necessary, wouldn't it be better to continue what you are doing that brought your footprint down, but then quit burning unnecessary fuel also?
And if you say you care about the environment, but buy "carbon credits", you are just a liar... especially to yourself.