UK at the moment its strange where the Professional operators are very heavily regulated with certification and annual renewals, assessment etc but there is zero regulation on the hobby side....well thats not strictly true as the regs do exist in form of BMFA and CAA documents and they are basically the same as for professional use but are generally ignored.
Most rc flying fields have a segregated viewing and a flight line a reasonable distance to keep high speed flying objects clear of people, suddenly MR's make an appearance and are generally flown in the public domain in the large part by poeple who who dont know regulations exist and have been sold a camera drone and who on earth wants to shoot video or stills of an RC Flying field.
Perhaps if some sort of permit and registration was needed it would make people more responsible, as they would then be aware of the regs and need to accept accountability.
The idea of having hundreds of potential 'dropped objects' and flyaway FOD as is already happening wont be tolerated for very long, take Spain as an example who have just suspended all UAV operations, and here in the UK the CAA are starting to investigate and prosecute offenders as a concious direction of policy
