Hundreds of steganography tools already exist for making images which can be shared on any medium where recompression is not an issue (http://www.jjtc.com/Steganography/tools.html). In this case I wanted to provide a simple user experience and also handle Facebook's recompression specifically.

In the future this tool could be extended to other sites which recompress images when they're uploaded although it would certainly be a more confusing user experience.

I suspect it was the technical challenge involved. If he did it for other clients or email, he may not have had to support JPEG re-compression which is both technically difficult and necessary for Facebook compatibility.