What's the Point of Two Sinks?

Am I missing something??? I just never understood it... What's the purpose of having two sinks in the bathroom, especially right next to each other??? Obviously they say "his and hers", but why?  Why can't they use the same sink? Seven of us live here, and we can all share the same sink. Hell, there's seven of us and well all share one bathroom! But even if I was rich, I can't see the point in having two sinks in one bathroom... Are they just looking for something to fill all the space they have? I guess this is one of the great mysteries of a genuinely poor person X-D lol