Yes, the Kelty Cache hauler weighs 6 pounds.   But, those extra 2-3 pounds do not really matter - because of the way I use it.
When hunting, either on a multi-day/over night trip, or on a single day hunt, I do care about the overall weight of the frame and bag.  That's because that backpack setup stays attached to me for pretty much every step of every single day.  I'd prefer a 40 pound backpack vs. a 70 pound backpack, as would most.
However, when an animal is down, and the backpack setup is solely being used as a meat hauler, the weight of the frame itself does not matter to me.   Hunting vs. meat hauling are two entirely different activities.    So, for the frame to weigh 6 pounds or 3, that is irrelevant.  How it functions is key.    On the way from the vehicle to the carcass, that is usually a minimalist setup (frame, water bladder, game bags, knife, half day's worth of food.)   In that situation, it doesn't matter if the frame weighs 6 pounds or 3 pounds, because the total weight is negligible.   Wearing a 16 or 13 pound backpack to get to the animal does not make any difference; it is a couple hours to half day's worth of hiking.   And on the way back from the carcass to the vehicle, the frame is fully loaded up with meat; it does not matter if the total weight of the backpack weighs 106 or 103 pounds, for instance.   The rigidity, comfort level, and load-hauling capability is the most important thing at that point.
If you'd like to haul elk quarters with a 10 ounce kids backpack because it is the lightest frame available, have at it.
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