Your a customer so you should be able to send them positive or negative feedback, if I was a regular customer and they told me they couldn't hold it for a couple of hours I wouldn't be doing repeat business with them. It's not like someone is going to rush in and buy the bolt of fabric within an hour or two.
At my LQS I always try and give positive feedback to the shop owner about classes I take there, the various teachers, etc She has class survey forms but it's not the same thing as having her regular people tell her that the staff is doing a great job. Feedback is everything in business especially now with so much online buying.