An example of this is found in some retailers in N America. If you walk in off the street as a complete stranger, prices displayed are high. Sign up for a store chain loyalty card and agree to being sent 'useful marketing messages', and the more you shop, the lower the prices, thus locking in customer loyalty. Part of this of course involves the retailer being able to 'monetise' the data about you and not just your purchasing history but also details of any product enquiries you may have made.
US Retailers also sgement on basis of how many returns you make as well, i.e. the lets buy the pretty party frock for 1 night and return next day bint gets classified V quickly.
If the price displayed to the customer is substantiallyaffected by web browsing / purchasing / Facebook / Google+ history, then Ryanair need to be very careful - Ryanair may end up doing the commoditised low-profit-margin high-commercial-risk flying while more of the value in the airline business accrues to Google. I do not believe Ryanair are remotely capable on their own of making use of the value of big data / data science.
No but why would they need to when people like Dunhumby etc would do all of that segmenting for them.