Programming is pretty lucky that there is also large demand for programmers, and the product is high grossing, because the salaries are good. Most other fields with a passion component are low paying. Almost all of the arts Film, Music, Writing, Art pay very low if you are not the absolute top of the field. Millions of people are out there writing short stories, drawing manga, shooting student films, etc for free to land jobs for salaries that the average CS grad would laugh at.