Yes, 'open-ended' to the point of complete meaninglessness. That's the point. If GSP-Hendricks, Shogun-Machida etc. fights - PPVs that did 500,000+ buys - are the standard by which we define a 'casual', then a casual is someone who is only aware of megafights involving a breakout star and thus would be unaware of 99.99% of MMA fights that have taken place.
So that means almost every single fight in MMA history qualifies. And because it is such a retarded premise, people took it upon themselves to list fights they actually thought were genuinely obscure. Try to keep up.
So don't worry, you don't come across as a dick. More just oddly emotional and simple.