No it doesn't always need repaired. If it's mild and doesn't affect the function of the penis, it's likely just a cosmetic issue.
I don't know about if the foreskin is always need if you do repair it though. Seems you could use skin from another body part, but if it's less sensitive skin, that probably wouldn't be a good idea since they need that sensitivity there. I remember reading about possibly using tissue from inside the cheek? Someone else will probably know more than me.
