I can understand not wanting everybody and their uncle (or aunt) making $ off of your design, but I really don't see how you can keep people from looking at the picture or the finished product and doing something very much like it even without buying the pattern. Once I see something, I can pretty much figure out how it was done and if I want to do one more or less like it, I can. Now even when I buy a pattern, I don't often do it just like the pattern anyway, so in one sense I've made it my own even with a pattern.
If I were going to set up a manufacturing plant and make hundreds of thousands of them, using their patten exactly, that would be a totally different issue, but if I'm doing several dozen over a period of months, and I didn't have the pattern or else modified the pattern to my own specifications, I hardly see the copyright issue as totally relevant.