In Today's New York Times, an article describes the burgeoning practice of leasing advertising space in state parks, and even the sermons of some ministers (link below):
http://www.nytimes.com/2016/12/02/opinion/sunday/mother-nature-is-brough...
For the sake of our individual and collective sanity, we must reserve certain (particularly public) spaces for quiet, stillness, and reflection. If we cannot go to a national park to escape the bombardment of commercialism and consumerism, where else is there?