One of my favorite fantasy authors is L. E. Modesitt. One of the reasons is because his world, while it is infused with magic, has a lot of realism to it.
A large part of that realism comes from the fact that most of his wizards have to have some sort of day job.
He’s got “black” and “white” wizards, and in a flip of the usual colors, the black wizards are generally portrayed as good guys, and the white ones are almost always portrayed as bad guys — despite the fact that he shows a sympathetic white wizard in several books.
Most of his black wizards are involved in some sort of trade. Two that spring to mind are a carpenter and a cooper (barrel maker). The white wizards are generally part of the ruling class of their nations, but even so, we see white wizards doing things like cleaning sewers (using magic, of course) and serving in the military.
To me, this seems a lot more realistic than a wizard with no visible means of income. What do you think?