I think you'll see many more corporate alliances/promotions in the future as United tries to max out revenue streams and/or attempts to provide discounted or free goods or services to it's customers to improve perceived value.

Many companies like to use captive marketing to get their product noticed/sampled. Sometimes they pay with $$$, sometimes just with free samples, or both and/or other agreements/barter deals.

There will be contracted ones (like the Pepsi deal), and looser ones, like this one.