Umm, you´re only partly right.
For example, if you enlarge the second, the KLM photo, it says the helicopter is used for flights to the North Sea oil rigs. So that would be an operation totally unrelated to the normal business of carrying normal passengers.
As for the BA, I imagine those were used for flights to the Scilly Islands, off the Cornish coast - again, not a shuttle in the sense you´re implying (i.e. airport -> city centre) but rather a normal flight to locations a plane can´t reach.
Another example would be Malta Air Charter who serve Malta´s only domestic route on behalf of Air Malta: Malta to the neighbouring island of Gozo.
Click for large version
Photo © Harro Ranter
I was on such a flight half a year ago, and it sure was an experience!
Anyway, the only real shuttle service I´ve heard of were the flights from JFK to Manhattan which some airlines provided for their high yield pax. (I believe Lufthansa was one of them.)