I did interviewing for my alma mater for a few years, but I don't anymore. Some of these "public service" things I used as a negative signal. If the student started talking about the week they spent in Honduras building houses and how it changed his life, or how much of a difference she made by starting a recycling club for example. All of that seemed cynically calculated for exactly the purpose it was being deployed for. What really impressed me were the one or two kids I interviewed that had worked real jobs -- not internships.

I don't know about other interviewers or the professional admissions staff, but that was my impression.