I have had this happen to me before. People who don't knit have no connotation of what it truly entails. In future I would discuss price before you embark on a project. I would also explain that a scarf is made up of thousands of handmade stitches. People tend to get it then. I am currently doing the Laminaria from Knitty for a friend and he gave me more than enough money for the materials $100 plus a bit extra for my time.