Money spells aren't always the first area where you start questioning the ethics behind magick (that would be love spells), but many people start to wonder about doing magick for financial gain once the subject comes up.
In fact, I've heard it so many times that I wonder if anyone is actually out there casting money spells at all. Well, I'm pretty sure lots of people are, but I do know that the morals behind them can make some folks a little edgy. So here are my thoughts.
Think of your witchcraft talents as a skill like any other, and I doubt anyone would feel you have to avoid using your earned skills to benefit yourself at least a little bit. Is it unethical for an artist to charge money for his work because it's unfair to the people who don't have artistic talent themselves? Should a doctor work for free after spending years in medical school?
Once you have mastered a skill (like witchcraft) there really isn't anything improper or unethical in using that skill to better your own situation in life. Again, there is a line between greed and need. Even just a casual "want" is OK occasionally as long as you don't overdue it .
It also depends on the nature of your spell. Are you trying to take someone else's wealth, for example? A money spell that takes this approach is in a bit more grey territory, but you will have to make that call on your own.
Overall, you just can't paint all money spells with the same brush. There is no one ethical viewpoint and my personal opinion is that there is nothing wrong with using magick for financial gain as long as you aren't being excessive or greedy.