I work part time at the LQS, and it is my understanding that pattern designers are hired by the fabric companies to make patterns as examples of the fabric line. I know my boss asks if there is a pattern to go with the fabric. Once a sample is in the store, we sell more of the fabric. Many of the fabric companies have free downloads on their websites. Hope this helps, and yes, it is very irritating not knowing what color each piece is.
Linda in Missouri