Corporations wouldn't spend billions on advertising/marketing for no returns. The problem is we have no idea what works. Every single experiment says it does _something_ and that's as far as we’ve gotten.

Corporations do make mistake, but probably not consistently spending billions of dollars for no gain. For instance, Coca Cola spends 4 billions per year [1]

[1] https://www.statista.com/statistics/286526/coca-cola-adverti...