It's this kind of detail that gives local flavor to a place.
I passed one of many autobahnkirchen on the way to the airport this morning. It was this one, on the A5 in Baden-Baden: http://www.3d-autobahnkirche.de/index_e.html. Here is another website, in German: http://www.autobahnkirchen.de/html/baden-baden.html.
It's a fairly modern-looking church.
http://www.autobahnkirchen.de/karte.html has a map of all the autobahnkirchen and autobahnkapellen.
A church in the rest area of the freeway. Why not? There are chapels in airports, after all.