Kute,
I knew I liked your style sir!!!
Yep just take what ya need and nothing more regardless of the pack you use. (except the occassional flask for a night cap here and there
)
But really I haven't found that I overly load up my pack when going light at all just cause I have 8K cu in of space at my disposal.
I think it comes down to experience of knowing what you need and sticking to that. Maybe those that take more are just new to backpacking and feel the need to fill it up? I'm not sure, but I would never suggest to get a backpack hunting pack myself that was even sub 5K. So long as it compresses down well with a low volume even then who cares. Often teh difference between a 7K bag and a 3K bag is less than a pound. When you are loaded with camp and deer and have everything strapped to the outside of your pack going through the devils clubs and alders catching on everything like a Beverly Hillbilly you'll be wondering if that bit bag is so bag after all