I don't know how it ties (directly) into the thread topic...but OMFG, is he ever right.
SO much can be saved by just planning ahead, your day. People going to (insert brand name of favored quik-stop) to get a Coke, or a bottle of Vitamin Water, because they're dry.
I carry water in my cars. Used to carry it all the time on my motorcycle. It's not hard - see those 2-liter plastic Coke bottles that accumulate in your trash? Rinse them out - and fill them with tap water, or your favorite bulk-bought, filtered water.
They're tougher than anything. Freeze one, it won't split. Run over one with the car, and the cap will break off, but the bottle itself won't split or crack. You can put a couple of those on the floor of your car, and when you want water, THERE IT IS.
It fits nicely next to your Stanley thermos, filled with your preferred brand of home-brewed coffee.
Going out? Sure, part of the fun of a Saturday out, was lunch, or brunch, or breakfast somewhere. WE ARE BROKE, ALL OF US. You cannot AFFORD it. Eat at home. If that's not practical - pack a sandwich, or a hard-boiled egg, or a nutrition drink. But plan.
The railroad taught me this - with its chaotic work schedule, that often had me on trips over Christmas Day or other holidays where when I got to the hotel, there'd be no food, no coffee, no nothing. Often not even a clerk - keys left in an envelope.
Now, being newly-poor, these lessons in how to survive chaos, are paying off.