Originally Posted by mahasamatman
Other than the fact that they like to stick their noses in lots of places they don't belong, why in the world would the TSA get involved?
Each passenger is given a boarding pass which identifies them as the traveller. For the same reason you can't go through security with someone elses passport.
If the plane went down for whatever reason, and the guy in 28B was found to be carrying explosive, they need to know who it was.