For many years, one of the biggest sponsors in MMA was a small, niche, industrial product. It was cheap and made the owner of the brand happy, so bought the ads. Arena naming rights probably aren't cheap, but at a small company there might not be many people who have to weigh in on the decision.

https://mmajunkie.usatoday.com/2014/01/so-what-is-a-dynamic-...