If someone could come up with a 3d printed primer that could be used with crushed strike-anywhere match head material, or maybe toy caps, it would make these a lot more viable.
Even as I type that out though I'm thinking the smell of that almost 100 percent plastic cartridge would be awful so maybe don't use it indoors, and the corrosive residue from either matches or toy caps would require a fresh water bath (and all the problems that brings with guns designed for smokeless only) every time you shoot them.
And we're back to "we need cheaper primers" again!