I remember my first quilting lesson where the teacher said don't just look at craft fabric, check out dress fabric and decor fabric. If I like the feel of the fabric I'll buy it. Most people, even those who say they'll only use LQS fabric won't know the difference. I make charity quilts as well as for friends and family. I make them to be used and if they wear through being loved I'll make the owner another.
If someone only makes quilts for exhibitions then I can understand they will want to use more expensive fabric. I feel it's an individual choice. As long as you enjoy what you're doing Have fun.