Oh, sweetie, you'll be better off for it.

哦 亲爱的 你们在这里会过的更好。

And most of the time, the world is better off for it.

大多数时候，世界因此而变得更好。

Or they won't, and you'll be better off for it.

否则他们不会的，你会因此过得更好。

In other words, if the giver gave the cash value of the purchase instead of the gift itself, the recipient could then buy what she really wants, and be better off for no extra cost.

换言之，如果送礼者送的是同等价值的现金而非礼物本身，收礼者就可以用来购买他们真正想要的东西，不需要额外花费就可以更好地生活。