I take pictures of my quilts and study them because that is where you will find the flaws for some reason. I put in a whole row of my sons quilt upside down...and sisn't even notive until the pictures when it was finished being quilted and everything!
If it is an easy fix, yes by all means point it out and leave it up to the maker whether or not they want to fix it:)
As in my case...if it is already quilted and finished...don't bother LOL!