How does marketing impact consumerism?

Marketing exists to instill in the mind of consumers the need or desire for products or services that those consumers might otherwise ignore. By advertising under the most favorable conditions possible for their products, businesses hope to entice consumers to purchase those products or services. The use of the phrase "under the most favorable conditions possible" is intended to illuminate the manipulative processes advertisers use to influence consumer decisions. "Fast food" companies such as McDonalds and Burger King, for example, use television and print advertising that depicts their products in the most enticing manner possible. Photographs of cheeseburgers or video images of individuals consuming cheeseburgers invariably show exaggerated images of the actual product for the purpose of influencing consumer eating habits. Similarly, manufacturers of cleaning supplies manipulate images to give the impression that those supplies work much better than is likely the case.
Tens of billions of dollars are spent every year by advertisers for the sole purpose of instilling in the minds of consumers positive images of products and services. The U.S. Centers for Disease Control, for instance, calculates that the tobacco industry alone spends well-over $8 billion per year advertising cigarettes and smokeless tobacco products. All of that money is spent for the purpose of convincing consumers to use those products. That is considered by executives of the companies in question money well-spent. And, that is the point of marketing: businesses anticipate that a good marketing campaign will increase consumer sales. The success of many such campaigns validates that belief.
https://www.businessinsider.com/10-biggest-advertising-spenders-in-the-us-2015-7

https://www.cdc.gov/tobacco/data_statistics/fact_sheets/tobacco_industry/marketing/index.htm