Yes, Joseph, I’m aware of what it says about matzdikei harabim. But these little children have no idea what they’re doing.
Are we careful to be mechanech them properly, to do it first without understanding, and then to continue as their cognizance grows?
Are we being mechanech them that they are obligated to be concerned with the welfare of others?
And might we do a better job of that by starting them out sharing and being kind with their own possessions?
Possession, or “MINE”, is something that even very little children understand. And sharing is a good way to start them on the path of being real ba’alei chesed.
I’m not sure what lesson they learn walking around with a pushka. Have you ever tried asking any of them, before you drop your spare change in, what they think will be done with the money? Try it. The results may surprise you. And may prove to you how far removed the endeavor is from any thought of helping anyone.