30 things I do not understand about airport security

I am a frequent traveller. A very frequent traveller. With questions.

1. Why can I not go through security with a flask of aftershave, but can buy all the aftershave I want in the duty free? If duty free goods are screened in a different way, why can my check-in luggage not be screened in the same way? (..)

4. How come I have to put things like a deodorant and toothpaste in a sealed zip-lock plastic bag, but no-one ever sees the bag tucked in my carry-on? (...)

14. How come I could get on a flight even though the boarding pass was not in my name? (...)