you can in fact put a couple of the matthews reversible 9' stands into a backpack. they fold down to about 22" or something. depending on the backpack,they may stick out the top, along with the umbrellas. I've posted on here before and shown step by step, the exact process.

i wouldnt put a camera and lenses into a standard backpack with them though.

the Kata Bumblebee has a laptop slot that holds these stands and umbrellas nicely, the side of it has a built in tripod foot holder and loop at the top as well. it is safe to carry camera, lenses and speedlights in the same bag. its rather expensive though.