I mean, it's not like an audi key is even toothed, it's flat on both sides and about 3/16" thick. It's a very square key that uses a zig-zag shaped internal rail for the ignition tumbler, as well as a challenge-response encrypted RFID transponder for anti-theft. An ordinary housekey would do more damage to someone if you sharply raked it across their skin than a smooth square audi key. But! Since it pops out when you push a button, clearly it should be banned.
Fucking christ on a crutch, people.
If perception of security is the main goal of airport security, then it's time to raise the bar on the audiences intelligence level.