Crickets won't live for long with calcium on them. I've thrown uneaten ones that have already been dusted back in the cricket enclosure, and they always died on me, where I end up with white bodies.
Also, the powder becomes a paste when it gets wet, which will bind to the crickets, suffocate them, and make a huge mess. I once had the mister spray water into the feeding cup. I ended up with a big ball of dead crickets and mealworms, where the calcium powder that was on them just turned into a paste and they all stuck to each other and to the feeding cup. Wet, soggy, sticky mess.