If you've got the wherewithal to grow significant wheat and an avocado tree to fruition, I would think you could afford to give out more than just one sandwich along the way.
But when would you have enough to start paying people? When the average return on the investment is $150K/year? Do you start paying at $15K/year? Should you raise more money and wait until you can fund $1.5M/year?
But the point is that using a long-term approach - you will be able to pay people orders of magnitude more than if you take the short-term approach.
Long-term becomes the short-term in the future ;). If some businesses had started such an initiative in the past, people would be getting paid in the present - consistently.
100 companies 100k each gives you 10 mill. Just the return on that on any meager performing stock can fully fund 1 SV dev, indefinitely. Or, you can withdraw a couple mil from the fund per year, fully fund the entire project for 3-5 years or so. Investment is just a way to stretch out the fund.
Long term vs short term