I completely agree that's how they would see Pete.
Don does fit in with them though, he has charm, incredible looks, and a "different" take on morality, style, secrets and the accompanying sense of mystery, and most of all, he wasn't trying, at heart he's also something of an artist himself, as well as someone who plays on what others need.
Don certainly saw them as "empty" and their lives hollow or maybe more like their lives are based on illusions, not solid ground. Which? They were, but then again, they were living pretty good lives, in contrast to, for example, the place Don grew up, or hardscrabble farmers, coal miners, janitors.
In many ways Don would have fit right in, and probably have done well, via introductions, and left them for something more solid later. Don though, was the very definition of an American Capitalist who was succeeding, earning it on his own meant something to him, he needed that hidden money, the bank accounts, the Caddy, all of it, to feel worthy.
In the final season though, what does he end up doing? In a way, a poor man's version of that life, no possessions, drifting, staying here or there, with his friend, or with the car racing crew.
Until money, fame, power, and creativity lead him back to the rat race...