I'm really sad that the terms "mook" and "midriff" never caught on, because they're still very useful for describing these people, when needed. Like, I want to note this bizarre mook invasion of True Grounds that just occurred, while I was sitting here. (They mean well, and are clearly friendly-friends of the clerk, but are still stinking up the place with all their mooking, such as the one with the reverse ballcap noting his surprise at the presence of a couch by pointing at it and man-squealing.) Well, they just left, anyway.
I used to call these people Chads and Jens, when I was in college, but those terms are probably even less useful to drop generally.