What's the ROI on ads anyway? I feel like ads are just a way to funnel money between corps. People who are forced to see ads are really not even the point anymore. This is like corporations subsidizing other corporations. Don't even matter that you buy that item being shown to you.
The thing is, it's only a ROI if any of those passengers converts to a buyer. The act of seeing an ad creates no value for the manufacturer unless they are converted to a buyer.
What you are describing is a market that has the consumer (ad watcher) almost completely removed from the conversion of capital. Being forced to watch an ad, in this case, only benefits the airline by their receiving ad revenue. The passengers are nearly supflourous.
United Airlines passengers to see targeted ads on seat-back screens ( www.cbsnews.com )