In much of the country, garbage collection is preformed by a giant corporation like Waste Management, or if you live in New Jersey, the Mob. But in New York City the trash is still handled largely by the City’s Department of Sanitation.
This setup seems to work well enough during most the year (garbage does not tend pile up in the streets as it does in Italy), but it has a serious benefit the one or two times a year there is a big snowfall.
Since the city already owns enough garbage trucks to regularly service every street, it simply slaps a snowplow on the front of each one when needed, thus eliminating the need to maintain a redundant fleet of plow trucks.
American pragmatism at its finest.