thats always the suggestion, but every computer and laptop can easily emaulate all those things+ more.. I see no reason to use a rasp for that
Of course, if it's to play at mainly at home then I agree it's not as interesting.
I can bring two old corded Xbox 360 controllers with my Surface Book 3 and play pretty much any console game on an emulator. My SB3 has an HDMI dongle that I got with my SB2, so I just struggle to see the point.
I bought an SNES Classic, and it sits in the box because I can emulate all those games, plus more, with better graphical quality and more features on SNES9x.
Another could be some type of a Twitter ticker tape display for your front room.