Just thinking out loud here ...
Has our plucky band of survivors checked the freeways for delivery trucks? If you get up on the freeway, odds are in and area of that type there are probably dozens of eighteen wheelers loaded with food and other supplies that were stalled when the traffic stopped. The trucks are locked.
Nice to hear about the water truck. I am picturing maybe a water delivery truck with the big bottles? Got to be more than one of those around. Also, all the coca cola and pepsi trucks all carried bottled water as well.
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