All conventional structures of present states, like law or license, is in fact an economic activity under the guise. It must get its funding from someone who shall pay the bill to balance the cost and profit. Take the law for example. A law that cannot be enforced is just a wish. To be able to enforce, it collects its funding from the law breaker in the form of penalty and from the law supporter in the form of insurance premium. When, in counterfeit case, a merchant sells a goods at the price of 100 dollars while it produces the goods at the cost of 10 dollars, once suit by the buyer, the law will punish the merchant to the degree that the overall profit is less than zero with a penalty of 95 dollar per buying; 90 dollars return to the buyers and 5 dollars go to the law's operation expense and capital accumulation. The gradually accumulated capital by the law structure is the source of the violent force that the law can enforce on the merchant if the merchant dares not to honor the conclusion; in old days, these 5 dollars could be really in the form of guns instead of money. Alternatively, all the merchants may collectively send 95 dollars to get licenses from a license provider who will audit the merchants periodically. If any merchant defrauds the buyer and is recognized by the license provider, the insurance benefit sourced from the license fee goes to the buyer.
Being economic activity, the state structure or the free market corporations are sure to emerge to solve the problem and they are not evil in their own right; the state structure must be originated from a private service supplier too. The only evil is the monopoly, the monopoly state structure, that one service provider abuses its capital to kick out other service providers then it goes "absolute power absolute corruption and inefficiency".
In case of the service with strong externality, people may have different preference for different goods. Alice prefers fire-fighting to environment protection and Bob prefers environment protection to fire-fighting. Therefore, Alice buys the fire-fighting service and Bob free rides Alice while Bob buys the environment protection service and Alice free rides Bob. Here the word buying is in fact donation or volunteer. If a strong externality service cannot get enough funding collectively, then that service is really not necessary to people’s want and its capital shall be allocated elsewhere; a huge national offense budget is highly possible the case. Further, if that service would be so critical that people could not survive without it, then people would simply go extinct and their irrational preference would be forgot by Mother Nature and some other organism would emerge to utilize the capital released by people; in other words, assuming people’s preference being rational enough after 50k years of evolution, hopefully there should not be the case.
There is already method to prevent the buyer to defraud the merchants as mentioned here, the free market of many competitive service providers and a donation/volunteer system is the other piece of solution to prevent the merchants to defraud the buyer after they receive the money. After all, the price will be adjusted just right and the free market society shall be the most efficient.