Earlier quoted context omitted.
4 million balloons and routers would cover earth. That's actually not a lot compared to how many cars and cellphones are manufactured every year. If each one is $100 dollars, the total cost is only 400 million - less than google fiber installed in kansas city ($1 billion).
Google is a business. They're only going to spend big money on a project if they expect to make a profit. Even if it might be possible in theory to provide coverage to the whole world via balloons, you'd have to be willing to lose a lot of money. From the standpoint of philanthropy, you would most likely get more benefit per dollar in other ways. For instance, the Gates Foundation has spent a lot in Africa on fightin…
Maybe they figure that each new person on the internet will have a good chance of being a Google costumer. Or maybe they'll charge for access in rich countries, but give it away in poor countries.