I ask you to consider the Orange Juice analogy. If you had pure orange juice would you leave it un-refrigerated? Not likely as it would spoil in a short amount of time at room temperature. Well the same is true with grape juice. No cooling and it will spoil. Don't get me wrong, there are places that do carry pure juice but they have coolers.
Simply stated, no Coolers.... No Pure Juice
And is pure juice better than a Juice/Concentrate mixture? It depends on the quality of Juice. In some cases, the mixture is better than pure Juice.
Back to the Orange juice analogy. we have all had bad Orange juice that is not from Concentrate.
Need I say more?