See the Pepsi Refresh Project of 2010. Where Pepsi redirected a sizable amount of ad budget (including super bowl ads) to community projects. They abandonded this strategy after a while because they lost market share.
This is the biggest large scale test of advertising I'm aware of. But it probably doesn't apply to all products.
This is the biggest large scale test of advertising I'm aware of. But it probably doesn't apply to all products.