While I understand that descriptive names currently shown in ManageWiki is newbie-friendly, power users might want to consult the manual on mediawiki.org directly, which uses the variable names (eg. $wgMetaNamespace). Adding the variable names would help those coming from the mediawiki.org manual to locate the configuration option (or find out that a certain configuration option is not supported) directly, without having to read through every option and guess if it's the same option that they just read on mediawiki.org.