I actually think this is the most intelligent business decision too. I don't think us hard-cores drive their ratings, but the casuals do.
And since they can't afford to put their legitimate draws on free TV, viewership wise I doubt it makes a difference if they put the elite talents or the just bleed guys on. I think viewership has historically been driven by what leads in to the fights.
And if you want to make an impression you go with the guys who will deliver violence.
I'll never forget their 2nd ever FOX card. Fucking Rashad Evans vs Phil Davis main event. Co-headlined by who you ask? None other than Damien Maia. And rounded out by pillow-puncher Bisping vs another wrestling blanket in Chael Sonnen. That card was long and boring. I remember getting my buddies together to watch it and one fell asleep, no lie. And the rest wished they had. That card did great numbers, but the next FOX card was a big drop and they never got back up to those first couple shows (novelty was arguably a bigger factor in that, but still).
When that card was put together I didn't know what the fuck they were thinking and I still don't.