Compared to (my impression of) north America I think there are some contributing factors:

• Less sprawl: Bakeries are usually in a town/neighborhood (which has more nature compared to the US, therefore also more insects) and not surrounded by a huge parking lot where no wasps would live. There are also many neigbouhring properties with different owners/occupants. So their nest might nor be on your property or even somewhere where you’d be able to locate it.
• (more) indipendent shops: I see waaaay less wasps in the baked good section in supermarkets here as well. Bakeries are usually not huge so it is just a short distance for the wasps to fly in a confinded space. Bakeries are also not usually airconditioned which would probably irritate wasps.
• conservation laws: Wasps are considerd a protected species in Germany and catching, harming or killing them without a proper reason can carry a fine of up to 5-65k€ depending on the kind of wasp and the state. In general wasp nests can only be moved by professional and licenced exterminators (and they only do it when necessary, like the nest being near a kindergarten or in an occupied builduing).