America hasn’t really made a dent in domestic poverty even though charitable donations are the highest in the world per capita. At some point you do need an organized government response to problems.
When's the last time you saw a church organize a street cleaning party, though? (or opening its tax-free building to the homeless?)
Churches may not regularly organise street cleaning parties, but I don't think that they consider litter to be one of society's great sins either.
[0]: https://www.baylor.edu/mediacommunications/news.php?action=s...
Here are like a dozen examples off the top of my head.
https://www.journeystheroadhome.org/pads-shelter-program.htm...
Many municipalities in Rome dispose of garbage through large bins placed on the street at the bottom of apartment buildings. Especially during the winter, these bins are not regularly emptied, causing piles of waste around them and litter being carried around by the wind.
The same happens with parks' garbage bins, with the added challenge that you probably can't pick up the park's garbage and bring it to the municipal bins... because they're already overflowing.
While preventing littering is a laudable goal, the solution is achievable by all of us. Just pick up a few pieces and ay and throw it away. If everyone who complained about littering did that, the problem would be solved.
Sure, there would still be litterers, but at least the neighborhood would be clean. I'd posit fewer people would litter if there wasn't already trash everywhere.