The homeless under Waterloo Bridge are perfectly entitled to their opinions and are free to express themselves - The Royal Family on the other hand are not.

Just one point here: Prince Charles has expressed his many and varied opinions openly on many an occasion - architecture, medicine. He also actively, and behind the scenes, sends of many letters - sometimes several a week to government ministers, advocating his point of view on this and that. This has been documented and recorded in the press on several occasions. Whether his opinions are acceptable or make any sense I leave to others to comment on. The point is that he is abusing his position as a prominent member of the Royal Family in doing so. Interference in plans for the building on the Chelsea Barracks site is one example.