Hopefully it'll be fairly easy to bodge the init scripts so that the Pi boots, fires up X (sans window manager) and have your own game set up a full screen GLES context. Strip out as much of the distro as you can, and there's your redistributable game image.
This is precisely the scenario we envision for Pi-finity! Having a fixed hardware and software baseline makes development much easier, as anyone who has done game console, OS X, or iOS development can attest. This is true all the way up to the ultimate in embedded hardware and software. When the U.S. Air Force was developing flight control, engine, and weapons system software for the F-22 stealth fighter, they mandated that all contractors use precisely the same hardware, OS, programming language, ancillary development tools, etc.
The cost of software development constituted 75% of the entire cost of the development of the aircraft (not the cost of series aircraft production beyond prototypes) - yeah, three times the cost of developing the airframe, maneuverable-nozzle engines, stealth materials and structural configuration, avionics, weapons hardware, etc., combined.
Yes, there are definitely going to be aircraft flight elements in Pi-finity! I'm a fixed-wing and helicopter pilot, so, they're going to be very realistic.
The best things in life aren't things ... but, a Pi comes pretty darned close!
"Education is not the filling of a pail, but the lighting of a fire." -- W.B. Yeats
In theory, theory & practice are the same - in practice, they aren't!!!