Pretty much every mobile device in the world incorporates a 3.25% bundled patent license to Qualcomm's QTL branch off of wholesale prices if it interfaces with 3G or 4G mobile networks, regardless of if it uses Qualcomm chips or not. (In China it's off 75% of wholesale.) Most of Qualcomm's profits actually come off of this 25% facet of its total revenues rather than the 75% from the chips it produces, and Qualcomm has resisted efforts to break itself up into a more profitable licensing branch and a less profitable chip selling branch because it claims (probably correctly) that this process of chip development and patent filing is synergistic. Anyway, the parts that companies pick is afaik based on the cost, availability, and performance of the part rather than licensing considerations, though Qualcomm has more ability to enforce its terms if they are an important supplier in your chain so you might want to cut them out for that reason.
I'm not going to defend the 810 to the end since it is a flawed part, but I think the 810 is really only a B- part and not the D- minus part that some would suggest it is. I get the feeling that people's overly negative impression of it vs overly rosy impression Exynos is colored by something like extended runs of SpecINT2k or 3DMark on the chips. I've yet to see any reasonably holistic quantitative measure of whole SoC efficiency performance on the various sites that do this kind of thing that constitute a stress test of all its components, correct me w/ some data if I'm wrong. That said, the physical implementation likely trumps any design choices that went into the chip by a wide margin as well, so it's likely the 810 would lose to any 14nm fin-fet fabbed SoC, but my point is it would not lose by as much on tests that stress other bottlenecks like DSP, memory, and I/O than if the test just leans into one or two corners of the part.
I do think for now Qualcomm has an important edge in integration in packing its modem on die (I believe the 8890 has it on package) and just as importantly, making developers aware of its software stack for its various components. An aspect of this is marketing for sure and they need to do this as they don't make phones themselves, but this makes me think that their parts probably have better drivers and APIs than Exynos or MediaTek. It may not matter for Exynos if they decide to keep it in house just for the S7 and has just one set of developers for it, but I think they did have some teething issues w/ the S6 on the software side.