Why do coupon websites make me download a program to print coupons?

Coupons.com, RedPlum.com and SmartSource.com are three leading providers of online printable coupons. They all require you to download a special coupon printing software before you can print their coupons. Why do they do this when it seems like a hurdle for an average user?

According to Coupons.com:

"This safe software enables your computer to build and print coupons that will be accepted at stores."

RedPlum.com has a similar reason:

"The coupon printer helps RedPlum and the manufacturer manage the overall distribution and security of coupons and offers in circulation."

SmartSource.com provides the most detailed answer:

"The Coupon Printer allows for high-quality coupons that will scan at the retail store register. It also controls the number of coupons that can be printed in order to prevent fraud and protect the manufacturer."

In general, the use of coupon printing software is needed for accurate printing, quantity limits, and fraud protection. It is a small annoyance the first time you print coupons but remember you're receiving free coupons that can save you money on each grocery trip.