Travis runs/tests user projects, so there's nothing about it that's especially partial to Python 2 over Python 3.
>Your hate of Python 3 in every discussion about it is frankly baffling.
Or, you know, my pragmatic assessment of its popularity.
That you'd even use the word "hate" (when in fact, I like Python 3 over 2.7, even if its mostly tame updates over what 2.7 offers) shows that you're probably too partisan. I was enthused with Python 3 even when it was only a vision called Python3K back in 2000-ish. My personal preference has nothing to do with whether I see more people using it or not.
The situation is not unlike the perennial "next year is when Linux dominates the desktop", which has been every year since 1999.