Right, but it's not feasibly scalable or sustainable. It's like a pyramid scheme in the sense that only the person at the top (the one who owns/runs the app) makes a killing and then the people underneath are slaving away for pennies. If you have that much time, there are far better money making methods that will earn you more than $50-$100/month and over time could result in $500-$1,000/month or more.
If it was that easy, everyone would be doing it.
Read my response above, but one more thought... If you know people with "University Degrees" making less than $200/month (fine ~$210.19) then have them shoot me a PM as I'm always on the lookout for good VAs