Fair play, WalMart or Home Depot probably do just junk their carts instead of repairing them, I’ve only seen the repair truck (or evidence of their work) at regional chains. Come to thing of it, only on a style of cart (it folds 90 degrees, the red square on the top corner is the front bottom corner in use) that I haven’t seen anywhere else – maybe they don’t make that one anymore, and the store’s corporate office don’t want to lay out the money to buy 50-200 new ones at a go (per store) to replace them – they don’t nest with the more familiar style at all, so they’d have to replace them all at once. They’ve been getting the more common style when they outfit a new store or do a major remodel, which supports the preceding hypothesis.
Something else, carts that have been made in the last [I don’t know how many, 10ish?] years have been powered coated instead of stainless steel. Which, in addition to making them put off rust longer, would make a weld look awful since the coating would would have to be removed from the repair area.
Also, the newer casters have bearings with a guard around them to keep dust/rain/snow out.
These improvements might mean that by the time the you have wheels making noise, the cart is starting to get kinda ratty looking. Dirty beyond just being able to be hosed off. Chipped paint (powder coating), broken basket, cracked handle etc. Any of which is probably grounds for being taking out of commission in and of itself anyways at a Target/Walmart etc.
My first job was as a cart guy for Demoulas/Market Basket in the eighties. They had heavy duty supermarket carts and they sent them for repair regularly. I know there are/were companies that specialized in shopping cart maintenance. Market Basket might have done it in-house.
No, appending a six-foot broom handle perpendicularly will not keep customers from pushing them out of the store. This was true of the Rite-Aide carts. In fact, the broom handle was a vandal’s challenge. Once they had the geeky cart out in the parking lot, they zipped it right into the weeds! You’ll notice in smaller stores, such as CVS here in the U.S., that elderly and disabled people do frequently use those carts, and they want to be able to take them out to the car.
It would make sense in a throw-away society to buy throw-away shopping carts, and that’s why they’re so flimsy. You get what you pay for (the company).