Considering i was called a spoiled brat and told to shut up, i know what your talking about . lol but honestly its the same thing as in real life . some people just dont know how to hold their tongue sometimes. :)
Sometimes they're full of themselves, other times they're just full of "it". They may feel entitled because no one in real life has ever told them to sit down and shut up, or perhaps they feel frustrated because EVERYONE in real life tells them to sit down and shut up. Either way, it's really unacceptable, and those of us who see it take place will usually back one another up so no one gets "picked on" unfairly.
If you something you think is out of line or really mean flag it. But some people do ask really dumb questions and most can be googled or they can simply not click ask the people and get their question answered there. But again, you something you think is really mean flag it. People cannot call others dumb/stupid nor day duh or derrr on their answer (implying the person is dumb)