I agree with the concepts your are talking about, but I cannot imagine an IT shop failing to check the background of a system administrator who will be working with banking systems, for example. Think about the fallout if Deutsche Bank hired a database administrator with prior convictions for banking fraud, only to see that employee steal 100 million from the bank.
Of course it's checked for some positions, and finance is one of those. But in general, it's not legal to ask about it. If you apply as a programmer the employer can generally not even ask.
I'm going to bet that criminal convictions are pretty important in the relevant areas, even in Europe. They probably do a better job of discriminating which information is relevant and which positions are sensitive.
In general no. For the jobs I've applied to (electrical engineering for some pretty big companies) it's not been asked about. They have no right to ask, and no right to know. On defence projects the individuals participating has had background checks by the intelligence service, but failing that would not mean losing job - only not being allowed to work on defense projects.
In Europe they might not have to ask before running a criminal background check. And lying on the application might not make a difference when it comes time to terminate an employee.
In most European countries the employee have to sign and/or submit the application for a background check. The result will be sent straight to the employer, but the application has to be filed by the employee.
In Norway, I can not even get a written copy of my record unless I provide a valid reason. I can get it read out to me, but not in writing. That is to stop companies from asking without reason. The reason is printed on the record, and misuse is illegal. So if I get one for a visa application, and my employer uses that for anything but visa application, they look at civil liability for the information misuse, and criminal liability for the failure of threating information in the proper way.