As far as I understand, this should not be the case on an updated Ubuntu 14.04. It's true that fonts-arphic-uming and fonts-arphic-ukai are pulled, but as a result of the discussion at bug #1173571, for a few months Droid Sans Fallback has been the preferred font for sans-serif and monospace in the 69-language-selector-zh-* files. And the latter take precedence over the fontconfig files, don't they?
Which Ubuntu version are you using, anywnztj?
As far as I understand, this should not be the case on an updated Ubuntu 14.04. It's true that fonts-arphic-uming and fonts-arphic-ukai are pulled, but as a result of the discussion at bug #1173571, for a few months Droid Sans Fallback has been the preferred font for sans-serif and monospace in the 69-language- selector- zh-* files. And the latter take precedence over the fontconfig files, don't they?