An effect from Bellator simply existing has been the rise of UFC fighter pay, according to this article by Gross at ESPN: http://espn.go.com/blog/mma/post/_/id/18967/a-breakdown-of-alvarezs-bellator-re-signing
See the relevant paragraph here:
Alvarez's experience as a free agent isn't typical. But it was valuable.
"Everybody wants to know their true value and what they're worth as a fighter," Alvarez said. "It's a rare occasion where you get to go out and do that."
Alvarez said when the UFC offer became public, he learned of five or six fighters who immediately received raises as a result.
"That made me feel regardless of what happened, a little bit of power was put back in the fighters' hands and guys got raises," he said. "We deserve it. We work hard."