> In the aftermath of 9/11, the government has to be seen doing "something". This was the something.
No, that might have been true then, but the real reason is the same that Airlines suddenly unlearned how to group people who book togehter to sit together unless they reserve booking. The security theator is expensive to run, but it's less expensive than what you make selling more expensive methods of avoiding the security theather.
Airlines don't want you to have a nice and easy travel, unless you've paid the appropriate primum. They are perfectly happing intentionally pissing off 98% of their travelers to maintain the 2% who pay extra. And when you zoom out, that also means that what you pay for the premium tickets isn't to pay for extra luxery, its to pay for the intentional annoyance of everyone else.