Because they don't have a choice, given a choice, they would want to have warranty..
Saying no warranty buying the International version is not very accurate, because there is warranty. However, there is no local warranty. Two different things. This I believe have also been mentioned by other members previously.
As you said, it's a mater of choice. Some ppl feel more "secure" by buying/purchasing/getting something with local warranty, while others not so much, since they don't really care/not really bothered much about/with it. Yes, it's always best to have "warranty" (more on local warranty) for everything, but it's not a necessity anymore nowadays, just my POV.
