A compound bow is a fairly simple device with few parts involved. So, every major bow manufacturer has as many patents as possible to protect their designs and they all file patents on different designs to keep other bow manufacturers from making new technology. There isn't really any room for a new bow manufacturer to design, build and sell bows without infringing on some other bow manufacturer's patent. And by the time you pay the royalties for using other bow manufacturer's technology, you won't make enough money to stay in business.
Small cookie cutter bow companies just don't stand much of a chance unless they get lucky and develop some new technology and can file a patent and pimp out the technology and make money off of the royalties. Royalties are a big part of any successful bow manufacturer's income.