
Money is currency to replace goods, so that we don't have to carry around a basket full of chickens when we go shopping. No matter what we are trading, be it pieces of paper or pounds of pepper, you've done nothing to change the fact that we will have have's and have-nots, only the identities of those people.
Now: You've got this money. I've got this item. Wanna buy it? Well, this item is really popular and in high demand, and people are willing to pay more. You'll have to give me more money.
After: You've got this item. I've got this item. You want my item? Well, I don't really need your item, but you need mine. You'll have to give me five or six of yours for one of mine.
If it ever came to that than it is up to the person whether they would still want to make a deal like that or not. They could always find someone better to barter with. Not the case with our currency system today. The prices are set for everyone, if you don't have as much money as the next guy, than you're not getting the item, period.
In a barter system, things can be worked out. In the end everyone comes out happy because a deal has been made where as there is absolutely no bartering involved in our current system that's in place at the moment. It's, "You don't have the money?" "Get lost".