I see that as a positive, not a negative. Since the pellets can be sold, investors are more likely to invest in the development of the process. And the extra volume of production tends to increase the efficiency, i.e., to reduce the cost (paid by altruists and governments) of producing the pellets that do end up in the ground or in ocean trenches.
Yes! They’re called solar panels, and our best ones are about 4x more efficient than the most efficient photosynthesis processes in nature, afaik.