There is a lot of weird things going on with Mac's and windowing. When using LWJGL, I do not remember Cmd-Q ever working, I thought it was something that AWT added. In my experience, most fullscreen games in Mac (such as WoW) don't respond to Cmd-Q when in fullscreen mode.
The point here is not how to protect users from uncaught exception. It is more like: how to make a developer's life easier, in a world where unpredictable exceptions occur on a daily basis, while developing...
Writing just a bit of code to exit gracefully will help with development and will be nicer for users at the same time, although stopping the exceptions would be best
