I maybe should have mentioned that we also have direct deposit here for pretty much everything i.e. the bank knows where you're employed and how much income you make per month. I've heard from e.g. students without permanent jobs that they don't usually get this perk (anymore). But yes, it's essentially a credit card with very low interest rates, although I have a credit card as well and the debt is automatically deducted from my bank account at the end of the (CC billing) month. There is also a section in the online banking to view CC transactions even though it's a separate entity from the bank, so any changes to e.g. region locking, limits, etc. must be done via the CC website.

This (the bank knows where you're employed and how much income you make) is only possible with one account per person, right?

In the US people that do direct deposit are also treated differently by the banks. Both on the surface, i.e. you get better interest rates, and under the hood (fraud models adjusted).