I don't think it's silly at all, since a ton of people have suggested that you're paying more for Zipp than HED because of "advertising". I think it's worth pointing out that HED sponsors more pro tour teams than Zipp, and most likely their construction costs are lower. That's my take on it at least.
As far as the actual performance of the wheels (directed to no one in particular), I will say that there's more to life than aero. I've used almost all of the wheels mentioned pretty extensively. I ended up ditching the Stinger 6 because of fitment issues and the Stinger 9 because of handling issues (and I'm pretty much a ninja when it comes to handling deep wheels. High speed descents in a pack w/an S9=no fun). The braking of both wheels in the rain was also a deal breaker, and the Zipps excel in this area. If the new Stinger 9 is as wide as the S6 (which it seems to be), there are definitely going to be fitment issues with it. The S6 even rubs some FORKS, forget about brakes.
Lastly, while I was giving Jordan a hard time earlier, the fact is he was right on the facts, and has been more factually correct on the details of Hed's own wheels. There have definitely been 2 versions of the S9 out there, and Hed's representative has yet to even clarify that. I think some folks need to read the discussion a little more carefully before casting stones.