Responding to the emphsized portions.
There are a lot of NDBs still out there, granted everyday GPS is coming to airports like those, but most of AMF's airplanes do not have GPS. And even if the plane you are flying is GPS equipped there is a very good chance that you are only approved for enroute / departure / arrival operations and not approaches due not taking your check in a GPS equipped aircraft.
The approach into Siskyou, CA is NDB/GPS only, done that approach a few dozen times in a PA31...best part is that you don't land at that airport, but cancel and go VFR to the airport next door if the weather will legally allow it.
The approach to Vernon, TX is NDB/GPS only, done that approach a dozen times in a BE99...
The Caribbean is filled with them, done several NDB approaches in the 99 and one in the Metro...
NDBs aren't a thing of the past, they are simply old technology that is slowly getting replaced. The vast majority of the rest of the world is still using them religiously for enroute and approach operations.
Also, you will do DME arcs at AMF in IMC as well
, oh the terror!