Not Indicating !

I've broached this subject before, but the no indication clan seems to be growing. I have recently noted Police cars that don't bother. But this morning whist crossing the road an ambulance  one of the. 4x4 types , stopped at the  'T ' junction then continued with out indication toward me. When will people realise this is a dangerous habit as well as lazy? It really gets my goat  grrrrr!