really? fucking hell! that's actually quite shocking!
When I went there once they were trying foundation on me, iirc NC15 is their lightest shade (or so I was told) but the girl tried 3 different fucking formulas on me, but all in the same colour and was going ohhh maybe this one will be lighter and I'm sittin there thinkin like wtf are you on bitch?!
at the end of the day (LOLphrase) mac are a make up company with clever branding/marketing and their primary reason for being is to sell. just because make up is from a certain brand or they have written pro on it doesn't mean it's gonna be any good. There are plenty of other brands that are rated more highly than mac.