The fashion accessory is strapless to stay in line with the way the game handles backpack items already. Minion version has folded straps. (Usually seen if you inspect/drop the item in EFT)
I always find myself snagging these things when i find em' in raid on dead scavs, and in the process, slow my friends down because I'm overweight carrying like 5 backpacks stuffed inside each other.
"A cheap replica of some 3-day assault pack with a MOLLE attachment system, adapted and enhanced by owner as much as their creativity allowed. Does not offer much comfort, and volume is far lower than that of a proper 3-day pack, but it's still a backpack alright."