Owner Info is a robust replacement for the limited (and hard to find) Owner section of the built-in preferences app.
In the event of a lost device or emergency, a helping hand is much more likely to notice an icon on the main applications screen. Owner Info also neatly categorizes important information that may be necessary to contact you or a significant other, or even assess a medical emergency. (Consider that a Palm has a much longer battery life than a smartphone!)
Or, you know, it can also just be that finishing touch to make your Palm yours. You decide!