Interesting comment- thanks for posting.Interesting twist on the leaving of carts. I'm one of those that will round up loose carts around where people leave them. Good exercise. However, at the local Walmart Neighborhood Market that I frequent, I saw a woman leaving the cart next to her handicapped parking space and offered to take it back into the store. She thanked me, but said she leaves it for other handicapped folks so they have something to hold on to as they go into the store. Evidently it is an expected practice as I've seen the cart "exchange" happen on several occasions afterwards. I now leave the ones near handicapped spaces alone. There are plenty more throughout the lot for me to chase down.
OTOH- recently read an article of someone getting caught regularly throwing bags of trash over a small overpass onto a dry riverbed in Southern Arizona. When questioned, the subject stated "he was throwing the trash for potential migrants after crossing into the USA, as there may be things in the trash, they might find beneficial.