With respect to the customer retention and 'share of wallet' articles, if this sort of data analysis is being undertaken by the airlines I frequent, what they do with 'adverse' analysis results is a complete failure. So much so, I assume they do no customer retention and 'share of wallet' data analysis at all (certainly at an individual customer level).
If they undertake any analysis, they really only want to know the 'answer' if the data shows that the customer is happy and 'loyal' (95% of our 'current' customers are happy). If they are not, airlines which have limited competition (like in Australia for example) are very happy just to cut unhappy customers adrift and believe that sending a couple generic emails a week will increase their 'share of wallet'. No more effort is evident, from the customer perspective at least...
Management are not interested why a customer is unhappy because it is most likely a decision that they made which has alienated the customer. The same applies with the 'share of wallet'. Why give the board any reason not to pay your 'performance' bonus for the year (even if both revenue and profit dropped in the year).
Fare data analysis will certainly increase in the future, but only to determine the maximum the airline can gouge your customers before they leave....