Knowing your customer

How well do companies really know and understand their customer base?  Certainly there is strong evidence of companies selecting a target market and working to deliver to meet the generic needs of this customer base but how much more than this do they really do?   Am I classified by my age, sex, job and location alone?  Does this explain that I like to do outside of these demographics?  My buying behaviour is more driven and influenced by these outside factors than the obvious ABC1 male type indicators.  Companies need to work hard using all the available "big data" floating around to understand for their customer base what are these common extra curricular behaviours that they can appeal to that really meet the hearts demands and not the minds that the basic demographic suggests. Epic customer experience means knowing me....really knowing me.