Is anything actually 'skin coloured'?

I myself own a lot of 'skin coloured' products. From concealers and face powders to tights, bras, knickers and even plasters, they all by reputation claim to blend into your skin tone and thus give the appearance of, well no appearance. NONE of these actually match my skin colour, yet we still buy into these products for their 'invisibility' against our skin. Are we mad? It's like buying glue that doesn't stick, or a hair dryer that doesn't dry hair.