Not only that, if we've become advanced enough to finally decide we should genuinely spend our efforts on exploring space, by then perhaps a humanistic consciousness could have emerged rendering war irrelevant.
Well it depends on the method of accounting you're business would need or want to use, but in a monetary sense, then yes, it can be counted as cash made as soon as the money, not the product, is delivered.
What if it was counted because the teacher thought making the deal was where they made the money, not in the classroom. They made their money in the 2 hours, but delivered their service afterwards, which doesn't contradict her guideline.