Neat idea, but not something I feel the need to do. Have had hard bags on other bikes that you could leave unlocked, and sure enough at some point the latch would fail and I'd see my lid flapping in the mirror and my stuff strewn out on the road behind me. If they were top-opening bags and hinged at the front I'd say sure, ride with them unlocked...but with a side opening bag? NO WAY!
As for the "hassle" of removing the ignition key, gimme a break guys. All it takes is a little forethought when you stop, and even if you do forget it's not like it's a difficult task to push down the key and turn it to the FFS position to remove it. If that is to much work for you, just keep your FOB in your jacket pocket and use the spare in it for gas and the bags as I do.
Taint rocket science folks...it's just a motorsickle.