The way taxis are managed at the airport frustrates me greatly, yet it is something that I can only put down to Thai thinking.
In most cultures, I would have thought that the aim is to get people in a taxi and on to their final destination as quickly as possible.
Yet, the Thai's have this time consuming process of having to line up, wait for a bit of paper and then get into a taxi. Often I have stood at the desk waiting for a bit of paper for several minutes, even though there are plenty of taxis waiting and taxi drivers standing around doing nothing. If everyone has to wait a few minutes, these delays add up and the queue starts to get longer and longer.
Anyway, having been to Thailand many times, I realize that common sense is not so common in Thailand.