The other factor is the purity of the carbon.
Industry does use CO2; cheaper CO2 is an amazingly useful thing. Who currently sells CO2, and why would they not want this competition, and what kind of lobbying are they willing to do to prevent it from widespread adoption, despite the significant economical advantage, and changes to markets it's adoption would entail ?
What people don't do, because most lack a comprehensive understanding of how things are vs. theoretical ideals that are not based upon reality, is FOLLOW THE MONEY.
The most crucial thing anyone could do politically and intellectually is be aware and involved in industry, and strive to be knowledgeable about what is done now, and how it's done, what it costs to do it, who's doing it, and how they spend the their profits to keep doing it.
It's sounds complicated because it it; there's an interdependence that industry relies on, and it's naive to think that important discoveries and new processes are going to result in anything revolutionary anytime soon, particularly when most people are stuck in a la la land of ideals disassociated from reality.
CO2 isn't a bad thing. It's actually an awesome thing. Stick that CO2 in a proper usable form where it's needed and amazing things happen. You can grow plants in a greenhouse twice as fast without ANY need for pesticides, for instance. You can manufacture things cheaper and more efficiently. The question begging to be answered is in who's best interest is it to prevent the inevitable for as long as possible, and why...