I took the shopping cart out of the room years ago, not primarily for this reason but because the shopping cart/baby strollers were constantly raced around the room crashing over other toys and children and I just about lost my mind after hearing myself ask the children to stop over and over. I bought a pack of 5 shopping baskets so they can still role play but without wheels

I find that the kids still pile things up into other containers like my toy boxes and tubs etc so I have really just come to the assumption that it is a certain age group that goes through this phase and once they are around 2 years I discuss appropriate ways to play....it's not that they can't pretend the mega blocks are giant veggies for making soup, but it's not okay to just dump every toy into one big container...just because. My group right now consists of 3 under 2 and 1 at 2 1/2 so we have a set time for free play were they can do what they want, I really only step in when there is to much out and have them put a few things away before getting more out. I have a set amount of time in our daily routine...more so for 2yrs+, where it is what I call "adult led" activities. That's when I encourage them to pick one thing to play with, or I set out stations and float between them helping the kids with more challenging activities. I use the hula hoop system when I am trying to teach the kiddo's to keep their toys from making it into every corner of the room but it's just to confine the toys to one area, all kids can play with the same toy in the same hoop at the same time unless it's a personal building project