If a newspaper sells more newspapers, their circulation increases. They can charge more to advertisers. Advertisers are willing to buy ads because they know a lot of people will see them. More advertisers will want to get in on the action, and you could potentially be getting even more coupons.
While I advocate getting free coupons, be it from the Internet, someone else’s newspapers, coupon exchanges, etc., it’s really important to shell out a little bit of money for a newspaper. Check into subscriber’s rates and ask for a discount. Some newspapers offer a weekend-only subscription. You know you make all that money back, anyway, right?
[Full disclosure: Yes, I have worked at newspapers before. I don’t work at one now, but they’re very dear to my heart]