Types and uses
There are many different types of coupons such as discounts, free shipping, first-time customer coupons, and free giveaways.
Function
Coupons can be used to research the price sensitivity of different groups of buyers (by sending out coupons with different dollar values to different groups). In addition, it is generally assumed that buyers who take the effort to collect and use coupons are more price sensitive than those who do not. Therefore, the posted price paid by price-insensitive buyers can be increased, while using coupon discounts to maintain the price for price-sensitive 
buyers (who would not buy at a higher price).
Grocery coupons
The grocery coupons have the advantage of being usable with most retailers and not with only one brand or store. As the other types of coupons, grocery coupons are intended for people who are willing to save money when purchasing groceries but also to direct people towards buying a new type of product which normally will not have as many buyers as with the grocery coupons. They may also be used to increase the sales of a certain newspaper for example, as many people who have discovered the savings they can do with these coupons, tend to buy more than just one copy of that newspaper or magazine.
Some grocery stores double the value of a grocery, especially for products that normally are not very well sold.
Welfare coupons
The welfare coupons are coupons given to people who are considered to be living in poverty or at risk of living in poverty. According to the statistics, 19% of people under 18 years, 11.7% among people 18 to 64 years and 9.7% for people ages 65 and older were in 2008 living in poverty in the United States. According to the U.S. Census, over 39 million people were living in poverty in the United States, in 2008 which gets the total poverty rate to 13.2%. On the other hand there are many social programs intended to help these people and whereas some of them provide cash payments for a certain number of hours worked in various activities, most of these programs provide welfare coupons that come mostly as grocery coupons.
The welfare coupons are intended to help people with very low incomes to be able to partially satisfy their nourish needs. One of the most popular programs that provide food vouchers to a certain category of people is Women, Infants, and Children (WIC). The program is limited to pregnant women and children under 5 years old and the grocery coupons may be used to buy certain products such as cheese, milk, eggs, and some breakfast cereals.
Fundraising companies may also provide welfare coupons for people who are willing to donate certain amounts of money or to adopt animals. These welfare coupons may come as discount coupons for various products or for buying food for the adopted animal.
