I think I can debunk this: red paint for some reason needs more coats than any other color (house painter speaking, step back!) At least with modern paint. Before Behr Ultra a deep red wall would almost always need three or four coats, don't ask me why.

Maybe they went with red paint because it was cheaper and they didn't know they would need three times as much to paint it. But more likely it was because red barns just look better against a green field.