While some cards earn a flat rate for every purchase — say, 1 percent back on everything — many other cards give you bonuses for using your card on certain categories of spending. (creditcards.com)
Most also give you bonus points for purchases in certain categories. (rewardexpert.com)
Other scammers with even tell you that they will give you a bonus of even 2000 dollars to impress you. (binarysoftware.org)