That's exactly what he was probably saying, and that's the same way I feel. For me, there's a difference between a guy in a large Oscar the Grouch costume and Carol (or another puppeteer) being there and performing the character. Which brings me to this thought... I PERSONALLY believe that How to be a Grouch WAS indeed written by Oscar, as Carol did write and draw the book, giving it that personal touch. It's the same as an actor performing a specific character (let's say if Paul Reubens were to be PeeWee in person, you'd belive he was PeeWee)... you really can't have that with cartoons. however, I do believe you can have a phone conversation WITH a cartoon, as long as the voice actor is on the other end. I had a great opportunity with that once.
But to me, it doesn't matter if it's Mickey, Scooby-Doo or Sonic the Hedgehog... a person in a big plastic and fur suit taller than you cannot be the same thing... even if the park employees were allowed to do impersonations and talk, they'd still be guys in suits... though, to be fair, with the princesses, at LEAST they're more realistic and to scale with real life. Though, it's not like it ISN'T fun to take pictures with them. I like that, and I DESPISE being photographed. Really, you ever want to take my picture? Dress up as a cartoon character. Best thing about conventions, am I right? And Disney's Imagineers are always striving to break then surly bonds of reality... but let's face it... reality is a VERY solid thing that cannot be broken. There is NO WAY Roger Rabbit and Toontown could ever exist in real life, no matter how hard you wish and try for it when you're a little kid. That said, Muppets break the bonds of reality a LOT more convincing with less.
I've said billions of times, I don't care if the puppeteer is looking straight right at you, your eyes NEVER go to him when he's performing. I saw Carol in person as Oscar (and kick myself for NOT asking if I could stay and get my picture taken) at a book signing... and Oscar was there... he was.
But then that gets me to wondering... WOULD we accept a park performer (someone who is a hired official, classicly trained puppeteer, that is) as Kermit or Piggy? I dunno if I would... I might... it would be a fun experience...