Zeni is used in Dragon Ball: Sparking! ZERO to unlock a variety of playable characters, ability items, backgrounds, and many more. This means that you would most likely always need Zeni as long as you ...

If you ask Super Shenron for more Zeni, he will grant your wish by giving you one million Zeni. One million Zeni is a massive amount that would take you quite some time to grind for yourself.