You may charge as much as you like, what these people are indicating is that in order for you to "justify" your costs, they would like you to explain your level of ability and qualifications, if you will.

If he wants to charge $8 for a fully xhtml 1.0 valid page, then its up to him I personally code PSD's to html/css myself. My customers come to me because they know what i am able to do. I am sure you will have a customer-base of your own that wants you because of your price and ability. All im saying is everyboday has their place in the market, and it does not mean we all have to charge the same!