admin/user/user broken after uninstall

I was using realname with content_profile as the source at one point in this project, client made some changes, we;ve got no need for realname anymore...problem is, my admin/user/user page shows no usernames now. i went through everything i could think of, remembered realname had been used at some point and, just for giggles, dl'd it, enabled and VOILA! my usernames appear on admin/user/user page again. disable, they go away again. anyone tell me how to fix this? i just don't get it at all. the db has their usernames obviously, since if i re-enable they appear, but i shouldn't have to have realname on the site and enabled just to make this page work...