Google Analytics appeared in 2005, and as far as I know as a tech person, they never marketed it aggressively.
How did we go from sometime in 2003, when analytics packages (no matter how basic) were downloaded from sourceforge or gnu or whatever and installed on your website ...
to sometime in 2015 when you're working for a small/indie tech company, your website is mostly working and you're thinking of doing analytics on your website and someone suggests to you "you should just use Google Analytics, everyone does it, it's what you do, why would you use something else or write your own" ... ???
Also if Google Analytics is so popular among web-backends, there must be other service-apis that backend-devs use without even a second thought?