I am like mickeyc, I have a couple of carts, strollers, ride-ons out all the time. Kids love to put things in the cart just like going shopping. I let them do it as long as they are not taking something that someone else was playing with. For the most part, they don't fight over the carts...they are used to having them out. I let them make a mess as long as it doesn't get to the point of being dangerous. I don't want to control their play or stifle their imaginations, so as long as they are not breaking things, throwing things, or stealing toys from others, I don't mind what they do with the toys.