These could consume the wealth of several billionaires, make a difference to hundreds of thousands of individuals, and still not make much of a visible dent in the scope of the problems.
Upon what are you basing this assertion? Wealth disparity is huge, and increasing over time. Specifically, the richest 1% of Americans own about 40% of all wealth, whereas the bottom 90% of Americans only own ~20%. This implies that "consum[ing] the wealth of several billionaires" would make a huge dent in wealth inequality, and could dramatically reshape society -- in both good and bad ways, depending on how the wealth is used, and depending on unintended consequences.
Also, depending on the problem you're trying to solve, "hundreds of thousands of individuals" could very well constitute your entire problem space.
These could consume the wealth of several billionaires, make a difference to hundreds of thousands of individuals, and still not make much of a visible dent in the scope of the problems.