Since I come from a region that likes to eat durian, here are my two cents’ worth of contribution to the discussion. Personally, I don’t find the smell of durian all that offensive (of course, it is a different story when it is in an enclosed space. In fact, in Singapore, durians are not allowed on the public transport). In fact, I enjoy the occasional durian when it is in season. It may be possible that different people may perceive the smell differently due to smell receptors as Darren suggested. Another reason I can think of is because of culture. Food and cultural identity are closely related. Eating and liking a certain food is sometimes a part of national and cultural identity. Having grown up in an environment where durians are common, I may find the strong odour more acceptable simply because I have been exposed to it since young. Likewise, I find the smell of some cheeses offensive because we don’t eat that much cheese here. This is probably the same reason why some food from other parts of the world can seem “strange”.
There are other things that smell different to different people too. I used to live in Vancouver, Canada and thought it was really strange that lots of people seemed to burn their toast. As we walked around, I could smell lots of burned toast. Eventually someone told me that it was the smell of skunks, and that no one else thought it smelled like burned toast, they all thought it smelled terrible!