I wouldn't be the first person to complain about malfunctioning shopping carts. That's old. Every comic in the known universe has a routine based upom wobbly-wheeled grocery transport. No, I'm here to praise these wonders of domestic engineering. Next time you have no choice but to take one of those difficult-to-steer offenders, I suggest you imagine that you're in a French supermarket and thank God that you're not. A French shopping cart is a copy of the American original except that the French thought that they could do better. The American cart has two wheels that are free to steer. The French thought they could gain even more maneuverability with four free wheels.
If you ever try such a cart, you'll find that the stress on your wrists coming out of a turn is enormous. Twenty minutes per week of this kind of shopping is enough to build corded forearms like those of the Governor of California. Even if you manage to handle such a cart, you'd better take cover if you see a little old lady heading down an aisle pushing a metric ton of groceries at full speed. You don't need to have read Newton to know that "A body in motion will remain in motion." Madame will inevitably roll out of the turn sideways, madly trying to outrun the cart and to get to the opposite side. She will generally fail and run into some innocent monsieur with a cart full of bottles of a delicate Mouton Rothschild (Appellation Controllé 1999). Cleanup on aisle numero quatre!!!! Yes, thank your lucky stars that you live in America where the non-lethal grocery carts only chatter, wobble and squeek.