If you look at the Wiki page, it appears that whomever (whoever?) owns Zucotti park has a pretty broad remit as to what goes on there:
On September 17, 2011, the "Occupy Wall Street" protest began using Zuccotti Park as a campground and staging area for their actions. Some of the protesters displayed a placard welcoming visitors to "Liberty Park", an informal return to a version of the park's original name. The organizers had originally planned to occupy One Chase Manhattan Plaza, but the plaza was closed.
Beginning on September 17, 2011, Zuccotti Park was occupied by protesters.
Because Zuccotti Park is not a publicly owned space, it is not subject to ordinary public park curfew. New York City Police Commissioner Raymond Kelly said on September 28, 2011, that the NYPD could not bar protesters from Zuccotti Park since it is a public plaza that is required to stay open 24 hours a day. "In building this plaza, there was an agreement it be open 24 hours a day," Kelly said. "The owners have put out regulations [about what's allowed in park]. The owners will have to come in and direct people not to do certain things." A spokesperson for Brookfield Properties, the owner of the park, expressed concern: "Zuccotti Park is intended for the use and enjoyment of the general public for passive recreation. We are extremely concerned with the conditions that have been created by those currently occupying the park and are actively working with the City of New York to address these conditions and restore the park to its intended purpose."
On October 6, 2011, it was reported that Brookfield Office Properties, which owns Zuccotti Park, had issued a statement which said, "Sanitation is a growing concern ... Normally the park is cleaned and inspected every weeknight... because the protestors refuse to cooperate ... the park has not been cleaned since Friday, September 16th and as a result, sanitary conditions have reached unacceptable levels." To protect and clean the park, protesters volunteered to sweep the areas of the plaza and posted signs urging each other to avoid damaging the flower beds.
Starting at roughly 1 am local time on November 15, NYPD began clearing Zuccotti Park. After a court order was released allowing them to return, police refused to allow them back in. Later that day, the New York Supreme Court that issued the injunction ruled against allowing protesters to camp or sleep in Zuccotti Park. At midnight on December 31, 2011 about 500 protestors clashed with police when they attempted to re-occupy the park. Sixty-eight people were arrested within several hours.
Steel barriers restricting access to the park were removed on January 10, 2012. On January 24, Occupy Wall Street protesters dropped their lawsuit against the city and Brookfield for the imposition of rules which prohibited their tents, generators, and other installations from the park. The rules restricting these items had been upheld in court and enforced in the park.
It appears to me that the entire justification for the NYPD going all postal on the demonstrators was a specific request by Brookfield Office Properties.
If occupy were to buy the land (through an appropriate intermediary), it would allow for the encampment to return.
Of course I would rename the park, my choice would be "Ratfuck Greedhead John Zucotti Park," but you could go back to "Liberty Park" as well.