The duffel bag has been reinvented many times throughout the course of history. Twice in my lifetime it has been the bag of choice to have slung over your shoulder.
Back in the 70s there was the local favourite produced by a New Zealand manufacturer, a humble affair, typically in shades of faded forest green, a mustardy yellow or a dark blue with contrasting trim, white piping and metal eyelets.
I most remember the green one, maybe because the neighbour's son had one that he used to wear as he rode up the street on his 10-speed bike.
Then, in the 80s, the TV series Fame followed Leroy and his classmates at the New York City High School for the Performing Arts. They all had duffel bags to carry their sweaty dance clothes. These bags were accompanied by a lot of pouting and door slamming at unsatisfactory auditions, as I recall.
Those bags were not humble. Yet the duffel bag does have humble origins, being a natural extension of the bed-roll, the knapsack or the swag.