Characterizing it as an "ad" feels a bit dishonest, as if it was an ad for some random product completely unrelated to the conference or the badges themselves. It was a shout-out to the company that made the badges! And that after DEFCON promised to give that company credit on the badge case, and then reneged on that promise.

Even if Entropic shat the bed so badly that DEFCON's takeover of badge production was actually warranted (I'm super skeptical of this claim), the badges still consisted nearly entirely of Entropic's & Dmitry's work. DEFCON's removal of credit from the badge case was deeply unethical.