TSA was always "paid to stand three" (and look like they're doing something useful).
It was mainly created as a last ditch effort to keep the airlines a float after 9/11. A lot of people might be too young to remember, but a large chunk of the population stopped flying out of fear after 9/11. So the government basically created the TSA out of thin air to keep the airlines privatized.
Now we're just stuck paying for security theater and securing airline profit margins.