The "jobbers" of that time were the obvious precursors of the "rack jobbers" of the 20th century, who, for example, served as middlemen between record stores and record labels, particularly at the local levels.
I think there have been people filling roles like this throughout history in a wide variety of industries. The terminology has changed, but the job seems to emerge wherever there are similar market conditions.
The "jobbers" of that time were the obvious precursors of the "rack jobbers" of the 20th century, who, for example, served as middlemen between record stores and record labels, particularly at the local levels.
I think there have been people filling roles like this throughout history in a wide variety of industries. The terminology has changed, but the job seems to emerge wherever there are similar market conditions.