When shopping resale does brand matter with children's clothing?

Today was an incredible day.  Lot's of customers and meeting some great new people.
As I was sitting here taking a little breather, the store had calmed down a little bit a woman walks in and I greeted her as I alway do.  Asked if she needed help let her know I was here if she needed anything.  Several more people came in and she walks up to my counter and says really harshly your prices are way to high and then compaired me to another consignment shop in the area and said I can't believe you want 3.99 for a junkie t-shirt from the gap and 14.99 for a knit dress. 
So let me explain, The junkie t-shirt you are referring to is from the Gap and retails for $24.00 and is still on there website.  It is a worn look as that is the way it is purchased.  The knit dress is from Hanna  Andersson and it is new and from last summer collection and retails for $38.00. 
She then proceeded to tell me she could go to Old Navy and get a knit dress new for$15.00. Correct you could but it does not compair to Hanna Andersson. 
So just to explain, I own a high end children's consignment shop and only carry high end brands which in the normal world you would pay 30-100 for each dress new.  I price them by how old the item is, condition (I only take an item if it is in mint condition), and wear. 
This customer got really snippy with me when I asked her to show me what she is talking about. I said I always welcome input.  I said certain brands sell for more and they are priced as such.  She said she did not care what brand it is and my prices are way more very rude and loud.  I was really interested in why she thought she could do better somewhere else but she would not even chat with me about it just was really rude and left. 
What do you guys think? Does Brand matter?  I think so... A Hanna Dress will outlast a dress purchased from some of the lower brands as far as wash and wear. 
Let me know what you think...