Not bad thinking, but I wouldn't use it as an SOP.
I don't OC. My experiences just don't tend towards it, first and foremost because it draws attention.
If my CC is printing, I made poor wardrobe choices, or I got caught in a serious downpour. Most likely would be the downpour, in which case I HAVE used this idea.
A cart could be a distraction or a tool. I'd see this as pretty limited, unless you have one of the Walmart butcher knife/machete attacks that seem to pop up every few years. The same could be said of the entire shelf of Chunky Soup, if your pitching arm is decent!
Overall, I guess I'd agree that anything can be used to your advantage, just don't stop with the shopping cart.