It would be pretty expensive in terms of time if I had to go grocery shopping every couple of days rather than every couple of weeks.

Because you see no other way to grocery shop than what you're doing right now.

https://m.youtube.com/watch?v=KPUlgSRn6e0

In my case I didn't go by bike, I walked to the local grocery store 500m or so from home.

You'd just pop in on your way home from work or from whatever you'd be doing in town.

5 minutes in a small grocery store, back home with a bag weighting max 10kg, usually 2-5.

This is close to impossible in many places.

Big business killed small living.

It's not that people can't imagine better ways. I'd love it if there was a grocery store a 5 min walk from where I live. But there isn't. It'd be a 35-minute walk. Some people live further, many miles, from a grocery store.

But that is not an immutable fact of life. It's not "cultural" either. I see the main reason there aren't grocery stores on every other corner to be single family zoning. Not wanting to have "noise" around your house, pushing any kind of business away from your neighborhood, and not wanting "shadows" pushing away denser kind of buildings that can easily support local business. Change the zoning, and the built environment will change, I would argue for the better.

Takes me 5-10 minutes max to get from my kitchen to the supermarket and back home, on foot. The streets are safe due to low car usage so if I needed something else while cooking, I could send my kids on their own from when they were about seven (prior to that I wouldn't worry about their safety but I would worry about them bringing the right thing back and not deciding to stop off in a playground).

Here it would take 35+ minutes.