I'm a tour guide at a top 10...my 2 cents...Assume that everyone you encounter is evaluating you, period. At some places it can be fluid - you just won't know which places until it's too late. This bit me in the a$$ at a particular school that everyone loves to hate, but will remain unnamed 😉 , when a student host randomly started pimping me with tough interview questions when we were supposedly "casually" hanging out the night prior to the interview. It was early in the season and I didn't have my canned responses polished up yet, plus this caught me completely off-guard, so I stumbled through some awkward responses. After that, he acted frosty toward me and I knew something was wrong. Turned out the dude was good friends with my student interviewer, who didn't even give me 10 minutes the next day. Gee I wonder why. 6 wks later = rejection. 😡 Anyway, that's probably more the exception than the rule. The more common scenario is that if someone in the group stands out as particularly obnoxious and/or inappropriate, this info can find its way back to the adcom. Just remember the manners your mother taught you: smile, say please and thank you, keep a positive attitude and avoid negative comments, and DO NOT make political, religious, or otherwise inflammatory statements. (You'd think that would be a no-brainer! But you'd be surprised.) Just my 2 cents, so take it for what it's worth.