Since I managed a LQS most of my stash is from there. Now that I am retired and $$ is in short supply am now sewing from my stash. On some quilts, I don't have all the colors that are needed so a trip to the LQS or online shopping. I stick with fabric vendor that I like and most likely order Moda, Marcus Brothers, RJR, etc. I have shopped at Walmart or JoAnns for novelty fabrics but mostly for Notions and sewing supplies. Only one of my quilts is hand quilted most of the others are either tied or machine quilted. Most of my quilts are donated to friends and or family members. I have five that I rotate on my beds.
I am not a fabric snob, it's just that thread count matters and I don't like a lot of sizing on my fabrics, I just like the hand of some fabrics more that others.
Fabric costs are a factor in what I buy and mostly shop sales.