"Of course, neither David or myself ever saw a penny from them; it was the early days of merchandising"

This quote by Robert Vaughn is referring to the early days of merchandising, when he and David were unable to benefit economically from their work. It indicates that they were unable to earn money from their efforts, regardless of the reality that others had the ability to do so. This might be due to a lack of knowledge or resources, or just due to the fact that the industry was still in its infancy. It is a reminder that success does not constantly come easily, and that it can take some time and effort to gain the rewards. It also works as a warning to those who are just starting on the planet of merchandising, that it may take some time before they have the ability to make a profit.