ATNotts, just to add to the complexity of it all: If you buy a seat on a ZB (Monarch Scheduled) flight through AVRO which is owned by Monarch's parent company and is a seat-only tour operator you are covered by their bond. If you buy direct from Monarch you are not covered by any bond. If you buy that same seat through a travel agent you are not covered by a bond unless it is the travel agent that goes out of business.
If it is confusing for people in the business just think what the consumer must feel, except that they do not seem to care as long as they get a low price.