yes - but I have to increase my reply to the required 10 digits...
Look at a typical Joanne fat quarter and compare to LQS fabric.
1. Hold both fabrics up to light.
2. Close eyes and feel both fabrics.
3. Cut both compare for fraying.
4. Machine sew three strips of each as if doing a 1/4" test and see which fabric after ironing gives solid 1/4".
I don't know what those differences mean in the quality and longevity of a quilt, as I am a beginner, but there are obvious visible differences in fabric, wherever it comes from.