The problem is that many consumers might not even be aware that its a decision worth researching. For example, in some areas of the US it is cheaper and quicker to order online through Walmart than it is through Amazon. But most users order through Amazon by reflex, not even considering if there is an alternative.
Advertising helps here. It tells them "look there is an alternative. Consider it!"
People go to Amazon for online shopping because Amazon pays to have a bigger web presence through advertising than WalMart does. Had there been no advertising on either end, you'd have a level playing field where people would have to discover the best / cheapest / most efficient online shopping on their own.
Seems strange that you think advertising helps here when you also claim that people are responding to advertising with negative outcomes.
The problem is that many consumers might not even be aware that its a decision worth researching. For example, in some areas of the US it is cheaper and quicker to order online through Walmart than it is through Amazon. But most users order through Amazon by reflex, not even considering if there is an alternative.
Advertising helps here. It tells them "look there is an alternative. Consider it!"