[sanketsarang]

You make a good point. But there is one more reason for advertising than just conversions. If Coca Cola were to stop advertising, it would free up substantial ad space allowing for their competition to advertise cheap. These large brands don't just advertise for branding/conversions. They plan their spend budget so as to actually influence the bid rate. This makes it harder for newer brands to compete and get any viable ad exposure at affordable prices.