Indeed, but for this kind of thing to make a serious dent in Facebook, it would need to include a photo hosting and sharing service. Which, unfortunately, cost money to hold the data, so you either need to charge for hosting, or collect revenue through ads or selling data (self-hosting would be nice, but difficult to get your grandma to do it)
But, maybe even a simple photo sharing service _that lets you share those photos back to facebook users_ might be the first crack in the dam wall