Touring a town on layover sounds like a great idea.
But, I don't see why such tours must be offered by the airport, nor do I see why the tour must be free.
There is a huge number of companies that offer airport transportation.
You could probably get a fun tour from a taxi, lyft or uber driver.
There are often city buses and trains that serve airports as well. For example in Salt Lake the Trax Train runs from the airport to downtown. The train would be more reliable than a tour bus.
Hi @yintercept,
Thanks for the comment!
I believe the reason why these free layover tour are offered may be for the following reasons:
For example, the Tourism Bureau of Taiwan is the one who offers and sponsors the tourism provided from the airport. They hope to entice returning visitors who may not have thought that visiting their city or country could offer interesting sites (i.e. like myself, I didn't think that Taipei could be interesting but now think otherwise).
The catchword in your post was the word "free."
Free only happens when a group feels that they can make up the expense by selling people on something during the free experience.
I love the idea of a layover tour, but I would scratch out the word "free" and look at options by local small businesses.
There is a huge number of "airport shuttle" companies. I suspect that most of them would be happy to give a tour. I have never been in a limousine. I understand that these companies are willing to charge lower rates for off peak use like a midday layover tour.
By using the small business approach, one is more likely to encounter local small businesses and connect with the lay over city in a more authentic way.
Going the small biz route also means that one can find a layover tour at every airport.