This is an update, maybe boring? Interesting? based on the shopping trolley experience at Costco, written 5 months ago but never posted, with a bit of occupational disease from design, thanks for reading!

My first trip to Costco for shopping, I found that getting a shopping trolley requires a coin, which immediately gave me a cultural shock. Back home, trolleys are taken directly, and after checking out, the trolleys would be left outside the counter or pushed to the entrance where a supermarket staff would come to collect them. Then there's the coin, for someone accustomed to cashless payments, suddenly needing a coin leaves one completely stunned. Having lived for 9 months, I still can't remember to bring a coin when going to the supermarket.

Here’s how Costco's trolleys work – insert a 1-dollar coin into the trolley, the safety chain gets unlocked from the trolley bay from the previous trolley, then after use, push the trolley back into the trolley bay, insert the safety chain into the previous trolley, and the coin is ejected back to you. Using a coin for trolleys is very common in Australia, not just at Costco, but also at Woolworths, Coles, and other supermarkets.

This design is quite ingenious. To get their coin back, customers have to return the trolley to the trolley bay, so trolleys won't be scattered everywhere, making it convenient for other customers to get a trolley and also preventing trolley loss; if not returned, the coin acts as a fine to the supermarket. Either way, the supermarket saves on the labour cost of collecting shopping trolleys. In most cases, trolleys left in public areas will be cleared by the government, which supermarkets also aim to avoid.

But soon, one can’t help but notice trolleys abandoned on the roadside.

It's hard not to wonder – do the coins really work? Who came up with this method?

My curiosity piqued, I made some interesting discoveries.

The invention of the shopping trolley was very pure. 80 years ago, in Oklahoma, USA, a grocery store owner named Goldman noticed that his store's customers would never buy more than what a shopping basket could hold. Eager to make more money, how could he encourage customers to buy more? Goldman's cunning little brain designed the prototype handcart, a basket with a handle and wheels that could be pushed around. At first, no one used it, so he hired people to push carts around the store, and real customers followed suit. Before long, it caught on, and other grocery stores started using it. Goldman hurried to register a patent.

Just like that, the retail industry was completely transformed by this little invention. As Mr. Goldman envisioned, customers were relieved of the physical burden of carrying items, their purchasing desire increased, and the amount of goods bought in one shopping trip also increased.

From the 1950s, shopping trolleys evolved with new designs and functions, such as seats for children.

In the 1970s, more user-friendly plastic shopping trolleys became widespread.

With the advent of the internet era, as we all know, shopping trolleys became a standard feature of all major e-commerce platforms.

The coin-operated trolleys used by Costco first appeared in Europe, with Aldi being a typical representative. I couldn't find the exact year, but someone mentioned "since I can remember, Aldi’s trolleys had a coin mechanism". Aldi's feature is to offer lower priced goods, and the coin mechanism helps them save costs to achieve low prices.

The implementation of coin-operated shopping trolleys by supermarkets in Australia is encouraged (but not mandatory) by the government, after all, trolleys being pushed into the street affect public areas (imagine the shared bicycles in China), it's uncertain if it has anything to do with labor. For Europe and Australia, the populace generally accepts it, it represents public etiquette and civic duty. But if it were in the USA, people would think the supermarket is collecting tips.

There are also some controversies: some people think the trolley bay is too far from where they parked, some believe collecting trolleys should be the job of store employees rather than customers, some don’t want to push them to the trolley bay when it rains outside, there are parents with kids who find it troublesome, some simply find inserting a coin bothersome, and then there are situations like mine, forgetting to bring a coin but planning to buy lots of ingredients and thus unable to use a trolley.

More extreme, in 2010, due to strong resistance from customers, Woolworths halted the use of coin mechanisms in some operational areas like Brisbane.

Then a personal interesting experience: once we forgot which coin to insert and stood at the trolley bay observing for a long time, a kind local came over to help us out. Another time, I saw someone unloading their groceries to return the trolley, and another person called out to them and handed them their coin to take the trolley away.

In Australia, daily life can almost be cashless, using a coin to use a shopping trolley clearly doesn't keep up with the times. Forgetting to bring a coin feels like going back to before Goldman invented the shopping trolley. And customers are already used to returning trolleys to the trolley bay. Might as well, like Asian supermarkets, get a trolley without a coin directly. If the aim is to prevent trolleys from being pushed onto the street, maybe consider installing tracking devices or regional restriction alarms. However, considering that large supermarkets like Coles/Woolworths only have anti-theft measures for a few expensive items, adding such a feature to shopping trolleys is probably a long way off.