1. The TSA is invasive security theater operated on the principle that the most effective placebos are those with tangible side effects, namely body scanners and palpable tension at ultra-vulnerable (targets in and of themselves) security checkpoints.
2. The TSA is a country-scale jobs program for poor, unskilled, and unemployable people who might otherwise join disruptive political groups that promise more resource redistribution.
I think the first two points are reasonable if not explicitly provable, but my third point goes off the reservation a bit:
3. The TSA-friendly luggage locks are one of many overt acts of submission that the members of the public undertake in order to travel with speed; there is no incentive for the locks to actually work or be secure, as their primary purpose is to symbolize obeisance. I imagine this may be the case because the TSA-friendly luggage locks are jokes to begin with, as anyone with a common file, rudimentary lockpicking skill, or bolt cutter could pop them open in mere moments... not to mention the misbegotten troglodytes who actually have the master keys and help themselves whenever it suits them.