>No market is 100% efficient
Anyone who has ever bothered to watch an ad break will be less than surprised by this.
Given that we actually have markets where people deceive each other pretty much all of the time and justify the lying as a matter of business principle, perhaps we should study those instead.
Don't get me wrong, these fictional markets are interesting, but a lot of time seems to have been wasted looking at them instead of looking at the actual economy.