[NutChusty]

Yes I have always wondered that, When I had my recent trip to Indonesia, I found many Indonesians ware sunglasses, but not Thai's. When I was in Thailand my former girlfriend wondered why I always wear sunglasses, I only take them off when my photo was taken. I think it could be a cultural or fashion thing.
Also I would like to note, when I was at my former girlfriends graduation ceremony, I was told by a police officer I had to remove my sunglasses as the Crown Prince was about to arrive, it's got something to do with Royal protocol, maybe this is why Thai's don't wear sunglasses incase a Royal drives past.