Anyone who has the ego alive is a black magician. Therefore, wherever the ego is, there is black magic, too.
Obviously some jobs are "worse" than others. Generally speaking, advertising will have more or heavier black magic than other types of jobs.
“Nothing is easier than self-deceit. For what each man wishes, that he also believes.” —Demosthenes
"Do not worry; cultivate the habit of being happy." —Samael Aun Weor