I believe there is only so much that you can do. You have to be able to draw a line at a good job for the money's worth. I mean you wouldn't do a concours detail on a 89 civic that the owner wanted detailed for $100. I tend to let the customer tell me what they want the finish to be and give it to them. If they want just a quick wax, i may throw in a quick polish to help out a little but not charge for it.
I guess not everyone had a detailers eye. As long as a car is shiney, has no dirt and is clean inside, I think many people are happy. I mean look at all of the people going to the local car was / wax places.
Just like you, I strive to inform people about quality work and perfect finishes but I guess you can't go wrong as long as the customer is happy.