Isn't it a wonder how babies find it necessary to explore their world with their mouths at exactly the same time as they become old enough to ride in the big girl seat of a nasty, dirty shopping cart? Well, as soon as I realized that Macy would soon be ready to ride in (an consequently sucking on) the shopping cart, I started looking at shopping cart covers. Then I said, "shoot, I got skillz--I'll just make her one!" Here's what I came up with. It works for restaurant high chairs, too. It's elastic all the way around, has a padded seat for her precious little bottom, little round leg holes, and slits on the back to either fit the cart's buckle through (which is still kinda yucky), or in my case, clip the buckle I made (see that orange thing around her waste?) to the metal slats on the cart's back rest. I used 2 of those key ring clips that look like rock climbing carabiners, and they work really well!
And now that I've perfected the design, here is her official Ducks cover. It's kinda hard to see in this picture how it would go in a cart, but trust me, it works! (I haven't made the slits in the back for the buckle yet)