usually, weidu does this to make sure you don't break yr install: if you re-install a mod midway thru yr install order, weidu will uninstall all mods installed after it, then reinstall the one you wanted reinstalled, then reinstall everything else. it does htis to prevent you accidentally corrupting yr dialog.tlk and ruining yr game.
in this case, altho you were installing it fresh, you hadn't deleted yr old weidu.log, and so weidu was assuming, naturally enough, that those other mods were installed - and so it 're-installed' them to keep the dialog.tlk order the same. moral of the story: if yr doing a clean install, make sure it's clean.