Any service requires investment, though. What pays Google, Bing, DuckDuckGo, etc.?

I’d imagine it’s a way to sift normal users that might turn into power users, so they stay in Google’s controlled environment. Or, since apparently Google can modify programs in the Play Store if they so desire, maybe it’s a way to increase the chance the user will keep using approved backdoors/tojans/spywares. Either way, I can’t recommend enough for people to use vanilla phones, and have some cheap, second hand one just for stuff you can’t use without Google Play.