All banks use a credit reporting agency, a seperate one. You never discovering this just shows you and those you surround yourself with have never had to deal with it. Thats nice, but also a privliged and ignorant position.
If you think banks always check your credit score then you are just wrong, plain and simple. In Norway you'll always be notified when someone check your credit score, along with what data was provided, who requested it and when.