[jillesvangurp]

There is no Walmart in Berlin; nor any similarly sized super markets. The closest thing would be Lidl and Aldi but they tend to be much smaller.

One feature of Berlin is that it is very spread out and people mostly don't use cars to get around. It has a center technically but it's not where people live or shop. All the action is in the dozens of neighborhoods and micro neighborhoods around this. You can walk for two hours without leaving what most people would consider the downtown area or reasonably close to it. These micro-neighborhoods is where you find loads of small restaurants, bars, art galleries, and indeed weird, specialized stores and pop up stores. There are many thousands of these all over Berlin.

Part of the reason is simply that there's a lot of space for small stores all over building. Most apartment blocks have space on the ground floor. That type of space does not make sense for bigger chains since the locations are wrong and the spaces are too small. So if you want to open a small store for whatever, you can without spending too much money. Most of these efforts are short lived for obvious reasons but some of them succeed or at least survive.

Given that Berlin is crawling with tourists, foreign students, entrepreneurs, artists, etc. pretty much any time of the year, there's plenty of business for small quirky stores selling whatever. You don't attract tourists by being a bland boring franchise in Berlin. Star Bucks tried to open up a branch near where I live. They pretty much got laughed away and got replaced by a Poke bowl takeaway within a year. Just not a thing when you have several of the top coffee bars within a 3 minute walk.

Post internet, retail is increasingly specialized. You get all the staples online. Amazon is huge in Germany and Amazon Prime is operating in Berlin with their full set of services (including groceries).