Nearly 400 million rebates-worth about $6 billion-are offered to U.S. consumers by marketers every year. But do consumers like them? Often rebates require more effort than a consumer is willing to make to receive the cash back. Critics of the promotional effort say that marketers know this and are banking on consumers' not redeeming them, resulting in extra income for retailers and manufacturers. Do you think rebate programs are ethical? Why or why not?