Good to see they weren't putting you in handcuffs. I've never flown with my mavic, but if I did, I would have thought taking the complete aircraft as carrying-on with the props would be be frowned upon. Power up, spin it up to max rpm in sports mode and you have a pretty scary hand weapon. It would certainly do more damage than the kids safety scissors airport security confiscated from my 5 year old's bag.
If I did fly, my plan is to check the props and carry-on the aircraft and batteries. After reading the above, I think I will remove the batteries from their lipo bags at the x-ray scanning.