Snarking is cultural vandalism. I have arrived at this conclusion belatedly. I have been guilty of snarking, and of enjoying snarks. In the matter of snarking, I spake as a child, I understood as a child, I thought as a child. But it has grown entirely out of hand. It is time to put away childish things. I must restore my balance, view the world in a fair way, hope to inspire more appreciation than ridicule. No doubt there will always be a role for snarking, given the proper target and an appropriate venue, and I reserve the right to snark when it is deserved, as in certain movie reviews. But in general I must become more well-behaved.
Roger Ebert is against snark. You've quoted him saying that snark is "vandalism." Well, he's close. Snark is street art. It's graffiti. It's something anyone can do, with little more than a release of pent-up air, and it transforms whatever you put it on. If you take any boring, functional building, and introduce some snark, it will look different. If you're bad at it--you're just doing it to ruin a bit of property and put your own name, to claim a mark on your target, to prove your own superiority--then it's petty vandalism. It lowers the value of the property and makes the community uglier.
But Ebert is overlooking the wonderful world of good snark. A carefully crafted bit of snark, used in just the right way, can change the world. Think of Banksy's better works; some snark beautifies the community, some carries a strong political message. This is valuable snark, and I hope Mr. Ebert recognizes its role in our society. What would Oscar Wilde have been without his snark? When Winston Churchill heard his opponent saying, "If I were your wife, I'd poison your tea," he had the good sense to snark back, "If you were my wife, I'd drink it." He didn't say, "Well that's an upsetting statement" or some boring, unsnarky rejoinder. And thank God for that! Jon Stewart out there may be snarking, but his Pulitzers attest to the fact that you can snark the day away and still be providing a valuable service.
But there is a trade-off. How does one become witty and snarky, if one doesn't practice? Jon Stewart is the first to admit, he was a terrible stand-up comedian. As a matter of fact, if you go back in the archives and look at Jon Stewart's Daily Show in 2000, there's a lot more of the bad kind of snark--the petty vandalism of cheap jokes. But he learned on the job, and nowadays he can snark with the best of them. He snarked "Crossfire" off the air, and that's a public service to us all.
As a resident of New York City, I sympathize with your desire not to see that petty vandalism. But I put forward to you that some snark artists are quite worth waiting for. To be sure, there's much more bad snark than good snark. But there's much more bad painting than good painting, much more bad television than good television, and many more bad blogs than good blogs.