Earlier quoted context omitted.
I invite you to start selling an insurance product whose sales pitch is "You will get some utility from this product paying for other people's roofs!" Is there some kind of theory of insurance they teach in business class where they explain this "discover the network" idea? It doesn't sound like the common definition of insurance at all. I believe the perfect information case you say wouldn't happen is exactly what w…
There are actually insurances that to some degree work proactively to reduce the risk of all its members in the pool. My home insurance offer free pest-control, because they know that if this is neglected, it will cost a lot more for them. Plus, it will be hard to prove that it was a cause of the home owners neglect. At the risk of getting political, (governmental) healthcare is another one, where regular checkups ca…
> At the risk of getting political, (governmental) healthcare is another one, where regular checkups can save you thousands in repair. It might look like a subsidy but in the end it becomes a net-benefit for everyone in the pool.
This is part of the theory behind the Affordable Care Act and its subsidies, in that the more people who have health insurance, the bigger and more diverse the pool, it becomes a win-win-win for insurers (bigger pool = good, more money, more customers, more profit) consumers (health insurance = healthier, better life) and the government and country overall (healthy population = better long term prospects for the country).
Of course, true universal healthcare programmes like the NHS simply abstract that away by removing the profit incentive entirely, cutting the insurers out of the equation and turning it into a more straightforward "the government pays for healthcare because a sick population is just a plain bad thing". It's as such not really a "risk pool" or "insurance" in any real sense, because the amount you pay into the system is completely disconnected from your risk of drawing out of it (and indeed, given the correlation of poor health and low income, likely inversely proportional).