I haven't purchased from Etsy. I do "sell" there. Though, I rarely sell anything directly through Etsy. I most of my buyers are from craft shows and farmer's markets.
I do like that Etsy gives me a store front. I would probably sell more if I actually promoted things there. LOL!
I don't like to buy fabric online because I have thing about being to see it, touch it, etc. I will buy a known to me fabric or supply but can almost always find it less expensive elsewhere. I don't buy quilting patterns, so I have no experience with them.