The above reminds of two other "do something scenarios"
Going to the hospital. Doc sees patient for something minor, the patient does not need anything but some time the get over their ailment. But patient feels they need something so the doc gives them something.
Getting your hair cut. If there ain't much hair on the floor many do not feel they got their monies worth - so a bit more gets cut even though it is not needed.
TSA operates in the same mode. Even if what they do, does nothing, they have to do something because something is better than nothing. Especially if something else happens because they can at least say we tried something even though it had no bearing on the outcome. They are very much a reactive agency.