Although MRTs enjoy an excellent relationship with both military SAR helicopters and civilian air ambulances, the majority of rescues are still carreid out on foot, with NO helicopter support.
Military aircraft. Although capable of being flown in the dark and in very poor weather, they have many priorities and will generally only be sanctioned in life threatening circumstances. They can be grounded at their home bases by poor weather or turned back en-route for the same reason. They are stationed approximately 1 hour flying time away.
Air Amulances. Based much closer, their operation is much more limited. Poor weather can ground them and they have NO night flying capability. The injured person has to be loaded with the aircraft on the ground and the engine shut down. This means they need enough flat ground to land on... not always easy to find.
If you're not injured then you are unlikely to be rescued by helicopter, and may be depriving someone in genuine need of a sparse resource