Since I have limited income, I do shop where I can get the best deal. And yes, even Salvation Army, yard sales, online, wherever I can afford.
I do try to buy local when I can, but not just fabric. What about groceries, appliances, ect? Do we first visit the big box stores for our purchase? Last year I bought my front-load washer from our local hometown dealer and was happy to do so.
I do think one problem for years was there was no competition, so the local guys could charge what they wanted and get it. Not so much nowadays.