> Also, It lets symbols inside the module call their friends by quux instead of foo_bar_baz_quux.
This is the main point in support of modules: they make you use names just like you are used to in real life. In a given context, shorter names suffice. When more contexts are involved, then you need qualifiers.
It's visually much easier to parse foo.bar_baz.quux than foo_bar_baz_quux.
Also, It lets symbols inside the module call their friends by quux instead of foo_bar_baz_quux.