I took my car to the whittier dealership, same B.S.
my friend removed the battery and like dorks !!! show our faces (with the car parked right outside their customer service office) with the stereo in my hands, giving them the serial number located behind the stereo. Told me the exact same thing "to prevent theft, they had to see it to believe it"
great customer service though, explained everything (step-by-step) and didn't charge us a dollar to give us the code. But was satisfied with everything in the end.
hahahaha only to find out that the code was in a small ripped piece of paper inside the glove box when i first purchased my current vehicle from the dealership. That was a smack on the forehead !