Customer Profitability Analysis and Management

How is this relatively new advancement in management accounting potentially a useful and powerful tool? What types of data must be captured and tracked that traditionally was not measured? How would this affect the way we prioritize certain customers vs. others and the way we price and provide services? (Side note: for those of you who travel by air frequently as I do, how does the recent strategy of traditional airlines like American and Delta to offer Basic Economy Fares relate to this as a response to low cost carriers like Spirit and Frontier?)