How do I get Key Ring Reward Cards to store other kinds of barcode?
It looks like they explicitly support a few hundred (650, as of this reading) rewards programs. So they don't support just every last bar code you might want to store, unfortunately. 

That said, they do show a Toys R Us reward card in their banner graphic so you'd think it ought to upload that one. My guess is that you should nudge them about the reward cards you haven't been able to scan: http://www.keyringapp.com/