that's where those 13 are
and i found another page that shows by color all who changes and who doesn't
i think that was on wiki
Lots of countries who don't change to summer and/or winter time.
Funny enough what I saw these were mostly poor and warm(er) countries. And a number probably close to the equator. I doubt it'd matter much then.
When I lived in Indonesia it was always dark around 18.00. It didn't get cold though.
At first it was odd, but you do get used to it.