How to start the car with key only...

Today I went swimming forgetting that the smart key was in my pocket. I mistakenly thought the unit would be sealed and would work when I got to my car. It did not respond when I tried to unlock the car, so I pulled out the little emergency key to unlock the doors. At first one dash indicator showed that the key was in the car (literally the icon), but then when I tried to start the car, the neighboring icon showed that there was no key present.

I formulated a plan with my friend to get a cab and then tried to start it again. The car obviously knew the fob was in there. Once I replaced the emergency key back into the fob and placed the key in the slot near the steering wheel, it started. I don't know if it just dried out enough or....

Is there any way to start the car with just the emergency key (EK)?
Must the EK be placed in fob for the car to start?
I usually start my car with the fob in the cup holder or in my pocket so it was curious to me that it wouldn't start without being placed in the slot.

Can anyone answer these question and shed some light on this. As it was today, I felt I could not even call emergency road service because they would not know what to do either, except tow the car.
Thanks.