the thing i find with aviation is that most people only associate it with jet airliners. The general population dont even think about a small cessna/piper etc when you mention flying, never mind the difference between a 747 and an X-air. so at the first mention of a 'plane crash' they imagine 2-300 people burning in a field.
but as for radio calls if you dont want them to turn up when you put down in a field then dont make the call! its sad that ATCO's dont get their PPL any more but its something we have to deal with.
myself, i would rather see 20 fire engines and amulances turn up than none at all, but at the same time they should be fed the correct information so that their limited resources arent tied up dealing with a non event.