I see nothing wrong with a roll call because when you post in your sorority's (or fraternity's) roll call thread, you assume that your sisters/brothers aren't going to dig up information on you and use it to stalk you or put it out there on a public site for everyone to access it. Personally, I can think of at least one instance where I pm'd a new member to GC to tell her to edit her post in a roll call thread because it had too much revealing information about her (chapter, year in school, hometown, and university email address in the
firstname.lastname@university.edu format).