Avoiding going native

Some years ago I listened to professor Hans Rosling talking on Sommar. He described how he figured out that the epidemic disease of konzo is caused by insufficiently processed cassava in the diet. Then, apparently to demonstrate the wisdom of indigenous populations, he mentioned that the local population know very well what causes konzo but poverty often requires balancing between not eating at all and eating potentially dangerous cassava. I was dumbstruck. Why couldn't the patients have mentioned that, as they were piling up in the hospital and the (presumably city-bred) medical staff were scratching their heads at the mysterious disease? Didn't the physicians think to ask, were the patients too intimidated by the experts to voice their own knowledge, or did they just not care, as long as they were taken care of?

I had a bit of the same feeling when I recently saw District 9. The aliens had been on Earth for almost 30 years, long enough for humans to have learnt their language, yet no-one in all that time had asked them why they were here. I first thought this was a major plot hole, but considering Rosling's experience, I wonder if it isn't rather an accurate and scathing assessment of human behaviour—we don't care about the motives of refugees that (literally!) descend upon us, we just do what we, for reasons completely our own, decide to be the appropriate thing to do.