Raspberry Pis also get put in to all sorts of places where an embedded board could be used, but the Pi is so much easier.

I want to build a digital picture frame with an e-ink frame that pulls photos from a server. The right way would be a low powered processor, but then I have to figure out writing the image, sleep states and wake up, setting up networking etc. in whatever programming language my embedded board supports.

Or I can just plug in a pi, and live with the always on power consumption.

It's not that I'm ignorant, but I have a limited amount of time and may prioritize project completion over doing it completely right.