Hey now, the Nazi's believed they were making the world a better place. This guy was just lining his pockets off the bodies of his customers. He's in a class of evil above them.
But, the ideal goal is to go from top down, and the allies would have had to kill a lot less rank and file Nazi's if they had been able to knock the top of the Nazi party off.
I think the quote of "I’ve never wished a man dead, but I have read some obituaries with great pleasure." it very fitting for this situation. Both that random nurse, and that nazi soldier are working for evil institutions. Being killed because you work for evil is a risk of the job. Sure, both the nazi and the nurse may be victims of circumstance, may have needed the money, or been inspired by some propaganda. That doesn't absolve who they're working for though.
Should you be killing nurses or nazis? No, you shouldn't be killing any one, just like you shouldn't be gassing children, or denying people life-saving medical care. When you change one side of that equation however, don't be shocked when someone decides to change the other.
But, the ideal goal is to go from top down, and the allies would have had to kill a lot less rank and file Nazi's if they had been able to knock the top of the Nazi party off.