True it is "Mehman Nawazi" but a part of our culture is also reciprocity, what these people are unaware that such actions deserve an "inaam" it is not expected but in the spirit of reciprocity given.
The criteria remains high because the Services has enough access to well rounded candidates and limited intake. It is unfortunate that it did not work out for you. Do not be disheartened, Inshallah you will find other ways to serve Pakistan.