It seems to me your opinion is based on either limited experience with good training, or on a lack of exposure to the scenario you're commenting on.
This is not like conducting training on revenue flights, dead legs, or otherwise as is often done in fixed wing ops, in aircraft where the third pilot is unable to see what is happening. In the mountain environment or on more complex machines there can be great benefits to the observing pilot. Particularly in an Astar or Medium where the observer can watch all aspects of the flight, in the 206/407, i would agree there is limited value. When you are the pilot flying during training there is a level of overload that is reached, and given that we in the rotary world do not generally have access to sims where we are able to record, play back, and analyse performance, and we almost always fly alone, it is on occasion a very valuable tool to use.
Not to mention it has ZERO to do with economics.
I am uncertain how you can be so bold as to say it is unequivocally all about economics when the company must train each pilot to the required standard, whether they observe as a third pilot or not? There is no cost benefit to the operator whatsoever, contrary to your statement. Is it a risk? Of course, every time we leave the ground there is a risk involved, but I would submit that in certain instances it is far more beneficial in the long term than forgoing the opportunity. There are a great many ills inflicted on pilots by companies all through our industry, but I can't add this situation to that list.