Names for software releases

Why does everyone these days feel the need to give every release of their software some codename. I can understand that for the case of operating systems for example. A new big release (not just an update) asks for a new name, if not alone for marketing purposes. But today I stopped by the Joomla website and they seemed to have released version 1.0.8. This version has been given the codename “Sunshade”. Why in the world is this necessary? Version 1.0.8 doesn’t sound like it’s the next great version, doesn’t it? Why can’t they just let is simply be 1.0.8?

Note that the version of this post is 0.2.5b. Also known as “butterfly”.