My Shelbie was Very light when she matured and she was beautiful! Alot of people prefer the light ones. That tech is by no means a yorkie expert and has probably only seen a few yorkies and the majority are darker. don't let it bother you, I used to hear it alot because Shelbie weighed 11 pounds.  so what, we all come in all shapes and sizes and colors even when we are supposed to be a certain way. 
 
 