[ergl]

Have you never heard of a shopping caddy? https://en.wikipedia.org/wiki/Shopping_caddy

They're incredibly popular here, and yes, all supermarkets will have a lock stand near the checkout area so you can leave them there and easily reach for them as you're bagging your groceries. They're also foldable and/or small enough to fit in almost any closet.

[bluefirebrand]

Those little things would definitely not carry a weeks worth of groceries. They barely look like they carry more than I could by hand

Never seen a grocery store with a lock stand for these things either

[ergl]

They can hold a surprisingly big amount of cargo if you pack things right. Here in Spain they're definitely used for weekly hauls of groceries, although it might be pushing it if have more than two kids.