The 1.5 million people living in Manhattan (not even counting those who come in to to work here) need toilet paper, popsicles, beer, vegetables, furniture, etc. to live. Additionally we need our popsicle sticks and empty beer cans hauled away. Trucks driving on avenues facilitate this.

I happily live without a car in Manhattan, and have for the past 20 years, but I realize that my walk/public transport lifestyle is facilitated by trucks which bring things to my local stores.