I agree with you, and have always felt that way. I have found some of the fabrics that I see in Walmart or Joanns in the LQS. In general, what you said about the 'feel' of the fabric is the best indicator of the quality of the fabric.
In any event, I think the maxim with regard to buying fabric should be: "Buy the best you can afford." If I can only afford sale fabric, Walmart fabric or Joann fabric, so be it.