I suppose they'd have about the same amount of interest as, say, a car manufacturer might have in recommending longer oil change intervals

...a perfect example being the Mazda MX5/Miata/Eunos Roadster. The Mazda recommended oil change interval jumped from 6,000 miles to 9,000 without any change to the engine design.

I think on average mine only gets changed every 15,000 miles or so. Probably not a good idea, but it has survived 115,000 miles over 6 years so far, I haven't killed it yet (though it has been off the road for the last week getting all the hoses and timing belt replaced after some well hidden and old hose let go on me the other day).