Have you not heard about paying fees to use patents? It is very common but is not done in archery much. Your answer would apply to every industry and so why does your thinking seem to not apply in all cases?
Because:
A- Archery products are a niche industry with pretty short product cycles, compared to other industries
B- There is a lot less margin in Archery products, compared to other industries
C- The RnD and prduction ramp up costs vs how long your product remains current in the market is significantly higher than a lot of industries. Can you imagine if Ford brought out a completely new F150 EVERY SINGLE YEAR. A mid cycle refresh, sure, but most motor vehicles have a generation run of 5-7 years before a complete redesign. Bows are closer to 1-3 years, tops. Your latest and greatest bow is only the latest and greatest for a relatively short window before the market demands you basically throw the whole thing away and start from scratch.
I mean, ford have been using the same engine in thier F150s since 2011 (albeit with minor improvements and upgrades over the generations)
Can you imagine if a bow manufacture released a bow with the same riser/cam/limb design for 14 years?
D- Given A, B and C, licensing fees have to comparatively lower than other industries in order to be appealing to outside manufactures, making them not worth it to the OEM compared to capturing a larger percentage of an already small market. a 5% increase in market share is worth way more (both in customer retention and overall profit generation) compared to the couple of bucks you get from PSE/Hoyt/Bear ect.
This is especially true when you consider most consumers tend to be brand loyal, so if you manage to drag a consumer away from a Hoyt and into a Bowtech, they're more likely to buy another Bowtech in 3-5 years when its time to upgrade