I'm gonna guess its because of stuff like this...
http://www.nytimes.com/2010/06/18/nyregion/18knives.html?ref=nyregion
14 Stores Accused of Selling Illegal Knives
By JOHN ELIGON
June 17, 2010
At least 14 retail stores in Manhattan — including major retailers like the Home Depot, Eastern Mountain Sports and Paragon Sports — have been selling illegal knives, District Attorney Cyrus R. Vance Jr. said on Thursday.
But under agreements reached with the district attorney’s office, seven of the stores removed illegal knives from their shelves, agreed to forfeit profits they made from selling those knives over the past four years and agreed to finance a campaign to educate the public about illegal knives, Mr. Vance said. In exchange, prosecutors agreed not to bring criminal charges against the companies.
The agreements came after an operation months long in which investigators from the district attorney’s office were able to buy 43 illegal knives, Mr. Vance said.
“Clearly, there are a number of stores and individuals who have been brazenly and knowingly violating the law in this area,” Mr. Vance said at a news conference, where he was joined by Christine C. Quinn, the City Council speaker, and Scott M. Stringer, the Manhattan borough president. “What makes these knives so dangerous is the ease with which they can be concealed and brandished,” Mr. Vance said.
The knives generally fall into one of two categories: switchblades and gravity knives. On a switchblade, the blade pops out at the simple flip of a switch; with gravity knives, the blades come out by a simple flick of the wrist. Carrying either of those kinds of knives is a crime under New York State law, prosecutors said. A spokesman for Home Depot, Stephen Holmes, said the company did not know that the knives were illegal in New York. As soon as prosecutors contacted the company, it immediately removed the knives from its two Manhattan stores and is removing them from all locations in the state, the spokesman said.
“These are common knives,” Mr. Holmes said, adding that contractors and homeowners often used them “for various home-improvement projects.”
“We simply didn’t know that they were being used for any other purpose,” he said.
At least seven stores accused of selling illegal knives to investigators have not entered into agreements with the district attorney’s office, but Daniel R. Alonso, Mr. Vance’s chief assistant, said he expected that all of them would ultimately cooperate.
Mr. Vance said he expected the forfeitures by the stores to total nearly $1.9 million. Just more than half of that money will go to the city, 10 percent to the state and the rest to law enforcement agencies, he said.
So far, more than 1,300 knives have been surrendered to his office, Mr. Vance said.
