If your employer didn't hire you and instead gave the $10 to aid, then it wouldn't have had a service or produce to sell and therefore wouldn't have gotten that $10 in the first place.

Okay... this makes some sense. I had to work it out like this before I understood it:

• My employer hires me
• I do work
• Employer gets stuff
• Employer sells stuff
• Employer pays me
• I kill people

But I don't really think this addresses the problem. In this scenario, whoever bought the stuff my employer sold just killed a bunch of people. So... my original question gets changed to:

• I work for an hour and get paid $10, but whoever bought the fruits of my labor just killed $10 worth of people
• I buy the fruits of someone else's labor and kill $10 worth of people

Obviously this is simplifying economy and labor and yada, yada. We could go into more detail, but unless you think the answer lies in those details I would rather not.