stupid are those that give stupid answers knowing that they actually have no idea what they say, and that happens everywhere around the globe. There are those though that simply say "i dont know", and you cant really call them stupid, just ignorant, which is not really a bad thing.
for example, i'd rather put my life in the hands of a doctor that knows jack about the country he's living, than in the hands of a doctor that spends half a day learning geography and doesnt give himself the time to learn all there is about medicine.
same goes with lawyers, architects, etc
i believe that for one to be a guru in what he does, he has to ignore some other things, this process it's called specialization, and it's a SMART one.