It's not just your town. I live in Dresden, which already has one of the highest "shop space per capita" values in Germany, and while they've stopped opening new malls in the city (out of sheer lack of space), every new building adds more shop space. In some places, it takes just 5 minutes to walk from one Rewe branch to the next one.
(Context: Rewe is a German supermarket chain. There are about 5 nation-wide supermarket chains and 5 nation-wide discounter chains.)
FWIW I think a big reason for this is also rent control. In Austria for instance many stores can't afford existing units because the moment a old store moves out the rent increases 10 fold. So many old stores remain in prime locations because for them still cheap rent exists and they sell old radios or similar things there because based on their rent this model still works whereas if the store were to close and be re-opened under a new owner they would not be able to continue that business model any more. These artificially low rents keep many stores afloat that would otherwise already have closed.
(Context: Rewe is a German supermarket chain. There are about 5 nation-wide supermarket chains and 5 nation-wide discounter chains.)