What if James Goodfellow, instead of foregoing new shoes, borrowed a different six francs to repair the window and then never paid it back?

The resources would still be consumed. Six creditors would each lose a franc of value, the same total loss. And Mr. Goodfellow would be less popular.

War has certainly fueled our economy in the past...

I cannot answer better than kleinbl00 and Ike have.

Also, with the exception of Zimbabwe, the newest instance of inflation mentioned in that entire Wikipedia page was 16 years old.

There were a few more recent examples:

· Turkey's revaluation of the Lira on 1 January 2005.

· Belarus experienced steady inflation from 1994 to 2002.

· North Korea most likely experienced hyperinflation from December 2009 to mid-January 2011.

· Romania experienced hyperinflation in the 1990s. The highest denomination in 1990 was 100 lei and in 1998 was 100,000 lei. By 2000 it was 500,000 lei. In early 2005 it was 1,000,000 lei.

With so many of the examples occurring in the last 30 years, one could argue that "episodes of really high inflation have become common" rather than "rare" if that suited one's rhetorical needs.

In the context of Bitcoin serving as a possible relief, I don't see why it matters if hyperinflation is rare. It could still help North Koreans and Zimbabweans.