I understand. It wends a bit, but the point is that growth is required by the use of extractive funding mechanisms. They say maintenance costs are the root of the 'ponzi scheme', but I'm not quite buying that. Modern cities are funded by bonds, and the bonds are secured by taxes, and the taxes are secured by force. No, the bonds are not the problem. The problem is that the spending can only be sustained through increasing use of force on an increasing population.
Strong Town's "growth ponzi scheme" isn't about bonds (from my understanding).
It's referring to the practice of inheriting or overbuilding infrastructure, and then being unable to afford the maintenance costs of that infrastructure because the surrounding area isn't financially productive.