When we got off the Colorado we found our friend's VW Van flat-tired. In the midsummer desert near Hite, UT, in the days when it was almost 80 miles of dirt either direction to the nearest pavement. Since he ran his tires down to cord to save money, and there were plenty of rocks on those roads, it was disagreeable but not really a surprise. He had one of those worm-insert patch kits and a bike pump. He announced that since he had the pump, we had to use it: fair's fair. So, it was maybe 105 - 110F, and while you may say you gain 0.2psi per pump, it's tricky to get the rim sealed all the way around before you start getting anything with the pump (if it matters, we used a circumferential rope with a trucker's hitch to squash it out against the rim), and there are still many pumpstrokes to get a completely flat tire up to pressure. Many.
I got a couple things from this:
1) It's in the category with commuting on my bike 6 miles each way at -10F. Done it.
2) Saving and investment, but the greatest of these is investment. Without that, you are in baby-bird territory: cheap, cheap.