I would assume (by reading the posters descriptions of the perpetuators!) that many, if not most, of the people cooking curry/"stinky" fish dishes in the microwave are from places/backgrounds in which curry/"stinky" fish is thought to smell *GOOD*.
Therefore, it is not so much an issue of some people violating "common courtesy", being "rude", "insensitive", etc ... but of people having different ideas of what smells/tastes good/bad. If you come from a background in which you've eaten curry your whole life and you and your family and your friends concur that curry smells, tastes, and looks delicious (which I would tend to agree with!), why would you automatically assume that other people at work would be bothered or disgusted by it? How can there be "common courtesy" when not everyone agrees on what is "courteous"? How can you criticize others of being "rude" when they may have no clue what it is that bothers you?
Now ... if we're talking about a workplace where everyone has sat down together and come to some sort of agreement or compromise about what is "gross" to cook in the microwave ... and then people continually violate this agreement ... well then, criticize and complain away. Or if we're talking about a workplace where everyone comes from an identical cultural background and therefore can be trusted to use "common sense" to decide what others might think smells gross ... yet people continue to cook this stuff anyway ... then fine.... But I suspect that is not the case for most of you all...