I have two different Facebook accounts, one with my maiden name and one with my married name. I think there's good reason for them because some people I knew with my maiden name (abusers and users) I wouldn't want to have them know my married name. Still, there are people who know both and are only seeing one of my accounts. There are certain things I share with each group, and certain things I refuse to share with each group. I'm getting rather tired of it, really. I feel duplicitous.
I guess what I'm saying is that despite how it could benefit us to have a different login so members would treat us like any other... there would be some amount of deception in it. If only that we conceal our mod identity. What we say as mods wouldn't affect us as members and vice versa... but, shouldn't it? Would it end up making us less accountable in some ways? If nothing else, it seems like it breeds distrust to allow it. Other members can't have two logins, and other members would wonder... hmmm, do you think X is a mod?