system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does Google get the money to drive Google Map cars all around the world without getting anything in return? What do they get from doing all that work and from all those expenses?
gpt
You have to remember that although Google has its finger in many technological pies, the vast majority of its income still comes through selling advertising. And to be a world-class multi-billion-dollar online advertising broker requires you to hold as much data as possible on the people who will be viewing your adverts -- the better the data you hold the more accurately you can target advertising, and therefore the more money you can charge your advertisers.

All of this is a roundabout way of saying that what Google gains from its streetview programme is simple: lots more people using Google Maps in preference to any other mapping product. The more people who use Google Maps (especially on an auto-geolocating device such as a mobile phone), the more data Google has about those people, which in turn it can use to boost its revenue stream as described in the first paragraph.