I keep hearing complaints from both New York residents and visitors alike that the city smells. You get used to it pretty fast, but it's true -- especially during the summer. In the two other cities I've lived in (Washington, DC and Baltimore) I would put the trash out in a specially marked bin or garbage can for pick-up. My apartment in the East Village has a designated bin on the sidewalk, but we seem to be an exception rather than the rule. Most people just stack their trash bags on the sidewalks, like so:
This contributes to the smell, and probably to the rat problem as well. So why doesn't New York require trash to be placed in bins like at least some other American cities?
This brief history of trash collection in NYC is fascinating, but it doesn't really offer an answer. So I'm stumped for now, but my best guess is that sidewalk and building entryway space are at such a premium that space-consuming trash bins have never been popular. If you have another explanation I'd be happy to hear it.