Plastic is the ocean's deadliest predator.
I make it a point to pick these up and bin them when I see them on the ground. Think of yourself as responsible for one bag a day, and save some marine creature from a miserable death. Also helps prevent our street trees from looking like filthy Dementors when tattered bags get trapped in the branches.
NYC DEP is piloting a couple of different approaches to trap litter at CSO outfalls and prevent these debris from entering our waterbodies. The pilot is currently being implemented in the Bronx, and a test in the Gowanus is up next.
Another approach the city should pursue is a wider rollout of the BigBelly solar-powered smart compactors which send out a signal when they are approaching capacity. These cans have greater capacity, allow for more efficient deployment of Dept. of Sanitation resources, and do not allow litter to overflow or blow away.