The Santas — and if you need to imagine a typical participant, just think of Billy Bob Thornton in “Bad Santa,” if the character were 24 and worked at Bain Capital — generally arrive via bridge, tunnel, subway and, perhaps this year, CitiBike. In the past, they have convened in Midtown and marched down to the East Village, where the majority of the day’s jubilations typically occur; those who were still conscious then took the train to terrorize Brooklyn. Chronologically, SantaCon lasts from about 10 a.m. until whatever time the last Santa passes out on a park bench somewhere.

Indeed, SantaCons of years past have been distinguished by sexism, drunkenness, xenophobia, homophobia and enough incidents of public vomiting and urination to fill an infinite dunk tank. Despite these rampant violations, the departing police commissioner, Raymond W. Kelly, recently praised SantaCon, claiming that it “makes New York New York.”

Perhaps most distressing about SantaCon is its size and the way that it shuts down and befouls dozens of blocks. Any East Villager (I am one) can tell you that the event makes doing absolutely anything beyond one’s front stoop an impossibility, unless you own swamp waders and a riot shield. Last year, an estimated 30,000 carousers participated in the festivities.

But really, it’s not the disruption or the noise that rankles. New Yorkers can endure street closures and inconveniences for any number of events so long as there is a beneficent impulse, or an obvious reason for the disruption. For a New York City event of its size, however, SantaCon is distinctive, and arguably impressive, in that it contributes absolutely zero value — cultural, artistic, aesthetic, diversionary, culinary or political — to its host neighborhood. Quite simply, SantaCon is a parasite.

SantaCon apologists point to its sizable charitable donations (a $10 donation to charity is required to “officially” participate), and the sugar rush of money injected to local business (especially alcohol business) owners. But the ends don’t always justify the means; and when the means include a neighborhood of kids having to watch simulacra of beloved childhood figures stumbling around, picking fights with passers-by — well, the ends aren’t justified. Charity is not a quid pro quo proposition.