One of the things that many tourists say after being in the Old City is "except for the Jewish Quarter, it's so dirty."
In fairness to the other quarters, it should be noted that the Jewish Quarter has been completely rebuilt since 1968, so if for no other reason, it simply looks cleaner and neater because it is much newer. It should also be noted that the Jewish Quarter also seems to get better municipal services.
Having offered that caveat, I want to add that the people in and around the Jewish Quarter don't seem to throw trash on the ground to the degree that people in the other quarters do. Now, that statement is an observation, not the result of scientific data gathering. I simply see what I see: People in the Jewish Quarter tend to not throw trash on the ground, while those in the other quarters have historically just thrown their candy wrappers, coffee cups, cigarette packages, etc, on the ground.
The Old City has several full time street sweepers, which probably accounts for some of the ease with which its residents toss their litter on the ground. Kids and teens seem to be the worst, but I see a lot of adult men modeling the litter dropping custom, too. I've also been told that in the Arab culture exists the idea that "what's inside my home is mine, what's outside is not." And this maxim probably contributes to the acceptability of simply dropping litter wherever one may be when there's litter to be dropped.
Further observation: While there is still a considerable amount of littering in the target area, the campaign does appear to be helping. I hesitate to use the word working, but slowly it might actually be working. Obviously time will tell, but there is already a noticeable difference in the appearance of Al Wad Road after the first month or so. And, to my great surprise, the cans are still in place and stocked with liners. I thought for sure they would have been stolen or destroyed within the first couple of weeks. I was wrong.