Found this toy shopping cart on a sidewalk with a sign attached that said FREE.
Put it in my car – drove to fort funston and gave it to True to play with. He knocked it over about 30 times, tried to get into it, dragged it backwards across the parking lot and then pushed it around for awhile. He likes to interact with new objects (or old objects) so he got right to work and then I started to pay him for all interactions with it to increase interest and then I paid him only for pushing it.
So he started pushing it more then dragging, knocking or trying to get into it.