The closest small one is about 1 km, a reasonably sized one for stocking up is 5 km or so. I have never walked to either in 5+ years of living here. Even the closer one is like a 10 minute walk (ish), and then I would have to carry back what I bought, which also means I can barely buy anything. 5 km is more like an hour by foot one way, so that’s just not happening, ever.

I usually take my bike to the closer one, or the cargo bike to the bigger one. I also pass by the smaller one on the way home from work (I commute by bike). The fact that I own bikes is why there’s never any rain to walk anywhere, basically. Additionally, there is very little sense in taking a (relatively small capacity) bike to a big store when a cargo bike is available. I also don’t own a car. I don’t know a single person who would regularly walk 1 km+ for shopping, but I also don’t know anyone who doesn’t own any form of personal transport. Most would usually take a bike, and take a car for bigger or heavier trips.

Taking a bus or tram/train for grocery shopping does happen for some, but highly depends on the local situation and town or city layout if that can bring useful time savings. Unless you live is the middle of nowhere, bus and train schedules are anywhere from every 10 to 30 minutes or so, more frequent in dense areas where there’s multiple lines.

Edit: for context, I live on the outskirts of a medium sized city (250k inhabitants), but my town only has 3500 or so. The small supermarket is on the literal other side of that town, the bigger one is one town over (opposite direction of city). Distance to the city is also only only 10 km or so (to the center), but there happen to be no “attractive” supermarkets in that direction for me.