Unfortunately, smart people with an opinion sometimes have a problem seeing the other side of the coin, and tend to see their point of view as the only right one.
A good example is yesterdays 'PHP is the right tool for the job' post.(http://news.ycombinator.com/item?id=5337498) The authors point that PHP is a great tool for getting something up and running quickly without having a lot of knowledge of servers and software was spot on, but he got a lot of hate from the HN community. As a bad programmer (programming is not what I do, I've only learned it to be a better manager, strategist and sparring partner) I can tell you that PHP is by far the easiest thing to get up and running for a fool like me. Yet noone seemed to accept this fact, and came up with a whole lot of 'ruby is just as easy, you just need to install [something I've never heard of, and probably wouldn't understand], or in python you just run [stuff I don't know] on the command line [which I haven't got a clue how works] and you're good to go.
These comments weren't meant to be mean, but from my perspective they were, because I'm at a very different skill level than the peolpe making the comments. They totally missed the point that PHP works for a lot of people because Ithey have no idea how a command line works, don't know how to edit configuration files, and don't care.
The problem isn't that people are intentionally mean, it's that some people are so knowledgeable in their area of expertise that they have problems seeing how it could be hard for others, and thus end up making remarks that seem mean, but really aren't meant to be.
I bet a lot of people on HN still don't see why PHP is so popular, even though the answer is unbelievable obvious. To me.