Each person runs their own business their own way according to the needs of the photographer and the client... I hate it when people Say " I would never do it that way" when they have NO idea what the needs of the business really are.
We go back in the business a long way, far enough that the 'normal' way of doing things for assignment work was to shoot the rolls of film and hand them over undeveloped to the client. Actually that has been the norm rather than the exception for large clients, with wedding and studio photographers being the exception. Big accounts regularly still work this way, with lots of photos provided to the client, and the client doing a final selection and having their own people do final touchup or getting back to the photographer for final touchup.
In any case, there has to be a simple way for others to view full resolution images in order to make decisions, and the thumbnail / preview is not enough, hence the need for a full resolution 'original'. And the easiest way to provide a 'universal' interface that works online and offline is via an HTML browser.