Eyeglass Frames

Two weeks ago I went with my friend at the mall ordering her new eyeglasses. I was wondering why at the mall since optical there always high price compare at other optical. I did not asked because it was her large eyeglass frames eyeglasses  not mine, but as soon as she got it I asked her how much she paid, and she said five hundred dollars. I couldn't believed she spent too much money for her eyeglasses. She told me because of this and that, but no matter what she said it was too much for me. I do not want to spend too much for eyeglasses that's ridiculous.