Once I went to my local supermarket when it was very busy and there were NO shopping carts in the vestibule, where carts are normally stored. Instead, there were several customers standing around waiting for a store employee to round up more carts from the parking lot and bring them into the store.

I thought, "fuck this" and I went out into the parking lot, grabbed the nearest cart, and pushed it into the store. I passed by those same customers who were still waiting (and looking mighty dumb, if you ask me).

Then it occurred to me: Why don't we always do this? I have to walk from my car into the store anyway, and it takes practically no more effort to push a cart while I walk than to walk without one. So now, when I park my car, if I happen to see a stray cart nearby, one that some lazy customer has neglected to park in the "cart corral," I will push it into the store. That way, I always have a cart. Plus, I have saved a store employee a bit of trouble. Plus, I have cleared a parking space for some other driver. Plus, I have gotten a little bit more exercise, which I need anyway.

If everybody did this all the time, the store wouldn't have to pay an employee to round up carts in the parking lot, and it would be able to sell food a little bit cheaper. And stores like the Arc wouldn't need to worry about people pushing carts into the parking lot and leaving them there.