Unfortunately, the attitude of many towards the press, humanitarians included and especially government workers, is often one of suspicion, if not outright fear.
Humanitarian missions are little different from any other public enterprise, diplomacy included, which is susceptible of misinterpretation by the public, hence ultimately of failure.
In my experience, problems most frequently arise from those who report for television, with little field experience in your area but an insatiable appetite for a sound bite.