Actually, it's not an attempt to discourage crafters...
It's a requirement by the licensor of the images that the fabric manufacturer print this on their fabrics. It's a limitation on who the manufacturer can sell the fabrics to. The manufacturer (and distributors) are not allowed to sell the licensed products into manufacturing situations.
Once it gets to the retail level, and thus to the crafter, the statements on the selvedge are no longer applicable.
To me this makes no sense at all, since what is printed on the selvage cannot be enforced anyway. Any requirement on the manufacturer would have to be spelled out in a written contract between the licensor and the manufacturer, not written on the selvages. I think Holice is right and we don't have enough information regarding what the fabric manufacturer is trying to achieve with this notice (other than irritating all of us quilters, and that is definitely not in their best interests).
Edited to add - and I'm still not going to buy any fabric with any restrictions printed on it, just because I'm irritated by it! That's really the only control I have over the situation, and I plan to exercise it.