Tony, oblivious, assumes that that's a friendly, reassuring pat on the back. Not that Steve's taping the social equivalent of a Kick Me sign to him.

"Thanks, Steve. I appreciate it." Here in the corner, at least, he can be out of the way without being too awkward about it. And he can still talk to people. Once he realizes that there are people standing around wanting to talk, that is. "Enjoy the rest of the party, huh?"