Think about it like this: In economics it's useful to assume perfect information so the market prices and clears and generally works. In the real world perfect information is extremely false, there's a cost to getting new information, a maximum processing speed for humans to digest new information, and a maximum amount of information humans can store (at or below max processing speed * hours lived).
Marketing (the advertising side) is the mechanism by which information is disseminated to consumers.
Marketing (the product-design side) is the mechanism by which information is gathered by producers.
Marketing is the mechanism by which the market attempts to overcome the lack of perfect information.
Marketing (ceteris paribus) reduces transaction costs, and thereby adds real value to the world.
Exploiting the lack of information _is_ overcoming the lack of information.
It might not be the most efficient net outcome, as a better solution might otherwise exist, but if there is an exploitable lack of information that is exploited then by definition the information in the system has increased.
Only if we believe that "exploiting a lack of information" necessarily involves increasing true (and useful) information in the system. I certainly don't believe that's true, much less "by definition".
Think about it like this: In economics it's useful to assume perfect information so the market prices and clears and generally works. In the real world perfect information is extremely false, there's a cost to getting new information, a maximum processing speed for humans to digest new information, and a maximum amount of information humans can store (at or below max processing speed * hours lived).
Marketing (the advertising side) is the mechanism by which information is disseminated to consumers.
Marketing (the product-design side) is the mechanism by which information is gathered by producers.
Marketing is the mechanism by which the market attempts to overcome the lack of perfect information.
Marketing (ceteris paribus) reduces transaction costs, and thereby adds real value to the world.