Maybe The Quilt Show and Missouri Star have a different contract than your local quilt shop.
The Quilt Show is Alex Anderson who is partnered with QS brand.
There are many online shops that sell QS rulers. Fat Quarter shop, Keepsake Quilting, Missouri Star, Quilt in A Day, and many smaller online stores. The quilt shops in my area sell them from their online shops too. I don't understand a company saying their product could be sold only to customers who pay in person.