Deceptive marketing

False advertising is the use of misleading, false, or unproven information to advertise products to consumers. One form of false advertising is to claim that a product has a health benefit or contains vitamins or minerals that it in fact does not. Many governments use regulations to control false advertising. A false advertisement can further be classified as deceptive if the advertiser deliberately misleads the consumer, as opposed to making an honest mistake.

Often used in cosmetic and weight loss commercials. These adverts portray false and unobtainable results to the consumer and give a false impression of the product's true capabilities. If retouching is not discovered or fixed a company can be at a competitive advantage with consumers purchasing their seemingly more effective product, thus leaving competitors at a loss.

Advertisers for weight loss products may also employ athletes who are recovering from injuries for "before and after" demonstrations.

An ad may omit or skim over important information. The ad's claims may be technically true, but the ad does not include information that a reasonable person would consider relevant. For example, TV advertisements for prescription drugs may technically fulfil a regulatory requirement by displaying side-effects in a small font at the end of the ad, or have a "speed-talker" list them. This practice was prevalent in the United States in the recent past.

Hidden fees can be a way for companies to trick the unwary consumer into paying excess fees (for example tax, shipping fees, insurance etc.) on a product that was advertised at a specific price as a way to increase profit without raising the price on the actual item.

A common form of hidden fees and surcharges is “fine print” in advertising. Another way to hide fees that is commonly used is to not include “shipping fees” into the price of goods online. This makes an item look cheaper than it is once the shipping cost is added.

Manipulation of measurement units and standards can be described as a seller deceiving customers by informing them with facts that either are not true or are using a standard or standards that wouldn’t be widely used or understood which results in the customer being misinformed or confused.

Some products are sold with fillers, which increase the legal weight of the product with something that costs the producer very little compared to what the consumer thinks that he or she is buying. Food is an example of this, where meat is injected with broth or even brine (up to 15%), or TV dinners are filled with gravy or other sauce instead of meat. Malt and ham have been used as filler in peanut butter. There are also non-meat fillers which may look starchy in their makeup; they are high in carbohydrate and low in nutritional value. One example is known as a cereal binder and usually contains some combination of flours and oatmeal.

...
Wikipedia