If you run a site that often makes snarky remarks, embraces controversy, and writes with a swagger, you're going to have a reflection.
That reflection will be found in the comments. The comments will be snarky, trollish, controversial, and reflect your own values.
You can try to tackle this by complaining about the problem, changing the commenting system, being less controversial, but that will significantly reduce the number of comments (and revenue from reduced visits).
If you were to ask the audience what they want, they would say they want deep, meaningful, analytical responses. If you were to watch what the audience does, they would post short, simple, and emotive messages.
The challenge here is two fold.
First, is your reflection a bad thing?
Is it terrible to have a community of people that constantly try to insult, troll, and otherwise provoke each other a bad thing? My first gaming community, the tragically named UKTerrorist, thrived on this. It was part of the culture. Members enjoyed it.
If it's not a bad thing, can you accept the community for what it is rather than what you think it should be? Members are simply satisfying their social needs rather than their informational needs.
Second, if you feel compelled to change it, you either need to attract a new audience or accept that you will lose most of the commenters.
Techcrunch is mistaken if it wants the same number of comments but not the same category of comments. Accept a quieter, more intellectual, discussion or a rowdier, flaming, discussion. Both have their uses.