Also consider the people that are not very good at programming. Like Me.
They may wish to programme for a small market like RISC OS and make money, rather than programme for windows and make nothing because there are tons of free apps or better programmers in windows land.
That is why I write apps for a specialist market (microscopy) or for PDA's. Indeed, many of my Palm apps were cracked and you can get them on a .ru site. That was why I eventually stopped writing apps for palm and now do custom jobs.