Since the inception of air travel, there have always been two main choices of ground transportation when travelers flew for business or pleasure. They could either take a taxi cab to their location of choice, or if they were on a tighter budget they could use the local public transportation system. It is the same in practically every country of the world. The taxi of course has taken precedence with most travelers because it is less complicated to take, requires less effort, and is quicker without the wait at the dozen stops and transfers along the way to reach a desired local address. So when a newer service in the ground transportation industry, like the airport shuttle service comes on the scene, it is often hard to fit it into what we already know.
The perception of a shuttle service is a connection in a convention center, or a hotel courtesy ride to the airport, but the industry has changed a lot in recent decades. The most recent evolution in airport shuttle service is a scheduled service in a privately owned 12 passenger van, that runs out of airports every hour or so, providing a connection to most local destinations of choice, either direct, or with very few, quick stops that do not require walking. In essence, the airport shuttle service captures the core need filled by a taxi service, providing reliable transportation to and from the airport, being simple, easy, and quick. But there are significant differences when we look at them both side by side.
Taxis are on a first come, first serve basis. Curbside taxis at the airport are usually organized and a line of passengers is formed to secure a cab. It can be very quick if there are few people, but can take a long time if there is a local event like a convention, boat show, or major concert or NBA, NHL, MLB, or NFL game. When there are great numbers of travelers flying in and requiring taxis to get around for meals and entertainment, the line of people to get a taxi at the airport is longer, and the line of taxis in cue to pick them up is shorter, so the wait could be several hours, and is somewhat unpredictable. The airport shuttle service on the other hand, requires a reservation, and is a scheduled pick up for a party with an exact amount of passengers. People requiring transportation in a hectic airport who do not have a reservation, are usually not allowed to get into a shuttle. On the flip side, when flying through an empty airport, people can find taxis available immediately as they exit baggage claim, and can find themselves waiting for another 20 minutes for their scheduled shuttle service.
The taxi service is private, where the airport shuttle service is shared. 'Private' is an industry standard term referring to the fact that there are no other passenger parties in the vehicle. The shared shuttle service is not private because a party of 3 can take up 3 seats and another two or three parties can take up the other 9 seats of the shuttle. Shuttles usually transport 2 or 3 passenger parties, and are often taking them to the same destination. Depending on personal preference, this could be a drawback for those who rather keep to themselves, or it could be an opportunity for mingling with others who have a commonality with them, whether they are in town for a vacation hotel stay, a cruise ship embarkation, or a trade show.