I hate grocery stores that use flagstones, cobbles, or corrugated carpeting as flooring for the area between where you pick up your shopping cart and the main sales floor. They do it so that you can't tell whether your shopping cart has handling issues until you've already walked so far that you're not willing to turn around and exchange the cart for another one. And even if you did exchange it, you wouldn't know if its replacement was any better until you went through the whole routine again.