Many moons ago in a place called the south the first Piggly Wiggly Store in Memphis, Tennessee opened. It was the first to have a supermarket layout where the public picked out what the wanted instead of the cashier getting what they wanted. They found out shortly after that if they wanted to sell more the customer needed something to carry their stuff in, so they used baskets, I assume a woven one. That quickly became burdensome as well so they had the idea to put wheels on them. Now what they called them is probably arguable but buggies were horse power vehicles so if I had to guess it was called a shopping cart since a cart was generally smaller and hand powered. I live in NC but spent most of my life in Vermont and I have never heard it referred as anything other than shopping cart. Both there and here. However, whatever it was called back then it was definitely in the south.