50/30/20 Budget

So I've been seeing a lot of posts about the 50/30/20 budget, which if you haven't heard is supposed to be a basic guidelines for a healthy budget at 50% of take-home being spent on Necessities, 30% on Wants, and 20% on Savings.

While I agree that this sounds like a healthy budget, its seems almost ludicrously impossible of the average person. I crunched my wife and I's numbers, and we're on like a 90-5-5 budget, how on earth could we only spend 50% of our pay on needs? Even with a paid off house I don't think we would be able to do that!