They could use a regular helicopter too if the drones aren't legal. I don't know much about the specific laws. I did a quick web search and there is mention of a new set of FAA rules being released soon so things may change. Right now the exception seems to only apply to people flying these things as a hobby but the rules require that you follow a set of existing hobby association rules like not flying carelessly or recklessly, avoiding prohibited areas, staying below 400 feet, keeping clear of manned aircraft and not flying directly over unprotected people.