I've spent time working with companies that do GDS systems (basically travel ticketing back-end infrastructure) and talked with a few startups in the affiliate/

I've spent time working with companies that do GDS systems (basically travel ticketing back-end infrastructure) and talked with a few startups in the affiliate/rewards space. Load management is also used a lot in business schools as a case study of how more complex pricing schemes can be used to extract a higher average price than would be indicated by a traditional macro-economic demand curve approach. Basically you're segmenting customers and also varying pricing based on available inventory. Airline seat inventory and hotel rooms as well are an interesting problem because they're essentially wasting inventory - if you don't sell a hotel room or airline seat before the day it's available, it becomes worthless. That's why airlines and hotels love to have reward systems where you're compensated with free travel/stays - it's a way to get value from something that might otherwise go to waste. (This is also why Priceline works - they are a way for hotels to get rid of excess inventory on a no-name basis.)