It's not so other people can see them, your phone will probably be at lock screen when you put it down anyway. It enables you to quickly glance at your phone and see the crap you care about.

From the home screen tiles I can instantly see if I've missed any calls, any unread emails, status updates on twitter/facebook, chat messages and text messages. Without scrolling, or tapping.

A scroll down the screen gives me other less useful stuff, like whether or not I need my umbrella today and if there is a wreck on my normal commute route.

Each to their own.