It's in a social media company's best interest for its user base to easily find and distinguish between Matt Smith the famous actor and the thousands of other Matt Smiths, especially the ones who might try to fake being the famous Matt Smith for shits and giggles and/or profit. "Verification" is definitely the wrong term for it, but if companies could come up with a different verb that didn't make even more obvious the divide between "important" people and the rest, they would have by now.