i think it's because silk is BOP whereas the other LW reagents are BOE. the birds eye view of mop crafting is that anything 'good' requires at least one BOP material.
http://www.swtor.com/r/Qzbjzl 7 day SWTOR trial with goodies.
The dude above me speaks the truth. Why sell satchels when you can just buy 496 recipes, buy blood spirits and sell some robes/gloves? On my server, the blood spirits cost 1k and the gloves sell for as much as 9k. That's 4k profit every 4 days.
Depending on how much you can earn for it I would say either save them or make bags for some alts!
I have 3 tailors right now and making these bags gives me a reason to log onto multiple chars. The daily rep grinds arnt bad once u get the 2x bonus.
I am keeping all the bags for my self (until i get 44) and as I level toons up (including more tailors =]) this will only get better for me.
nothing but empty space here bro. move along now.