Coupon Crazy Websites?

Hi,

How do these websites that offer daily/weekly/etc discount coupons for 20% - 40% off the product price make a profit?

I'm guessing that most websites mark-up their product prices by 10%-20% to make a profit, but if they keep handing out all these discount coupons it's basically bringing them back to break even or even a loss?

Unless, they over mark-up their product prices by 40% - 50% this way even if a discount coupon is used they can still make a profit?

Thank you,

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