It is absolutely not necessary to use fabric from the LQS. The important thing is to find good quality, not the location of purchase. There are many folks out there who will tell you that because it is $10+ a yard and from the LQS that this guarantees quality. In my experience this is not at all true. In fact, one of the worst fabrics I've ever worked with in terms of fraying and bleeding was from a LQS. What you want to look for is the feel of the fabric, whether you could see through it or not, the way the print looks, etc.