This morning my wife and I went to the store. After we came out the car wouldn't start. Everything else worked including lights, radio, locks, etc. I knew we had enough battery power, but the ignition button simply wouldn't start the car despite doing it's normal heartbeat light thing. Eventually I got it started after disconnecting the battery for a few moments which I'm assuming reset the ECU.

The ONLY thing we did differently today was me leaving my key in the car during our trip in to the store. Since there were two of us and I don't like my pockets full I left my smart key in the car and my wife locked the car with hers as we exited.

Is this some sort of security "feature" I simply don't understand?

ETA: I've now replicated this behavior at home. Lock my key in the car and it will refuse to start with that same key anywhere near the vehicle. Take that key 50' away and the car starts right up with my wife's key. To be clear, I'm NOT getting a "mis-lock" warning when attempting this. The car locks with the key inside but kills the ignition. Is that operating as designed? Reading the owners manual it seems like it shouldn't lock at all with a smart key in the car.