So what magical system did you have in mind that would suffer none of your potential problems? Even a publicly funded service is still as vulnerable. Services you run yourself still cost money and have their unique set of problems. The cost benefit to using APIs is that you're outsourcing that complexity to someone else in exchange for money so you can concentrate on your core business. It's why AWS is so popular. Yes, they could shut down, but the risk is worth it. Doing it all in house is the other risk... maybe your programmers can't develop the solution needed and your company tanks because you wasted a bunch of time and money building your own address verification service for fear the external API might shut down.
The USPS (which is quasi-private, I'll admit) offers address verification, but their service hasn't been reliable, which is why we have competitors now. Your fallacy is that because something isn't flawless that the whole system is a failure. And throwing around the word 'profit' as some pejorative, dirty word is an emotional manipulation. How else would people hire or expand if not for profit? The service I'm using (Smartystreets) now offers international address verification; I'm not sure how they would have paid for that if it weren't for profit. That extra money you bring home from your job after taxes and other expenses... that's profit. Your employer is living on borrowed time from the services you provide. What happens when you quit, change your rate, or become bored with your job? I guess it's worth the risk to them.
The USPS (which is quasi-private, I'll admit) offers address verification, but their service hasn't been reliable, which is why we have competitors now. Your fallacy is that because something isn't flawless that the whole system is a failure. And throwing around the word 'profit' as some pejorative, dirty word is an emotional manipulation. How else would people hire or expand if not for profit? The service I'm using (Smartystreets) now offers international address verification; I'm not sure how they would have paid for that if it weren't for profit. That extra money you bring home from your job after taxes and other expenses... that's profit. Your employer is living on borrowed time from the services you provide. What happens when you quit, change your rate, or become bored with your job? I guess it's worth the risk to them.