Test banks are prepared by the textbook authors and publishers, who intend them to be used by the instructors.
Using them is not lazy, a double standard, etc.
In my experience, this can work fairly well in elementary classes, and is useless in advanced classes.
Publishers often try to distribute test banks and homework answers in a way that will make them available to instructors but not students.
As we have seen, there is no way to do this securely.
In many courses, this wouldn't much matter. If it does matter, you'll have to make up your own questions.