You don't need to do your own edible printing to use the technology. All you need is someone to whom you can outsource it on an as-needed basis. I don't expect to ever need more than 2-3 sheets a year of edible printing (and as I've said many times, I refuse to own an inkjet anyway), so I just (1) gang everything I expect to need, including spares, onto one sheet, and (2) go to the local cake supply dealer.
And I happened to notice that if you can't find someone local who will do the edible printing, and sell you the unmounted sheet, you can outsource it to Debbie, at Icing Images, for only a little bit more than what the local cake supply charges.
At any rate, an edible printer has the same cost-of-ownership issues as any other inkjet printer: you use it like crazy, you go through ink like crazy. You let it go unused for too long, and it clogs up. So unless you're making money with it, an edible printer is probably going to end up costing you at least as much as outsourcing would.
HMM. I JUST HAD AN IDEA. NOT A VERY PRACTICAL ONE, BUT AN IDEA, NONETHELESS:
I know that they make edible marking pens. I wonder if a small flatbed plotter could be retooled to use them. No good for photographs, obviously, and as cheap as color printing technology has become, plotters have become a bit of a rarity these days, mainly used for cutting more than drawing.