There is a discussion that takes place with great regularity within any community of advocates. It builds from the eternal triad: (a) exceedingly wealthy people exist, (b) their wealth could change the world for the better if applied in the right way, and yet (c) they are not applying their wealth in this right way. Pick your "right way" from any of the paths you consider valuable - for me, it's generating meaningful progress towards the prevention and reversal of degenerative aging, the universal medical condition that kills more than 100,000 people every day. But perhaps you have something better, more beneficial to humanity in mind. After all, we're all very sure of the causes we support.
Some folk seem to thrive on the outrage they can generate by considering just how many dollars of other people's money aren't being spent the way they want. Others are deeply saddened and discouraged - but neither strikes me as a healthy way to view the world. Why should an advocate be perpetually worked up about those wealthy individuals who do not see the world the same way as he or she does? Perhaps because the advocate expects more from the wealthy than from the poor - and in many more ways than relate to size of donation.
What I mean by this is that I think there's a certain tendency to believe that wealthy people have attributes and talents that in fact they don't possess: they have a great deal of one important thing, so therefore they must have more of all the others, right? But across a broad spectrum of the wealthy, you are probably not going to see greater intelligence, drive, wit ... or vision. Wealth doesn't grant you any of these things if you didn't have them beforehand, and a few decades of being alive and socially active should teach you that none are a necessary prerequisite for becoming wealthy. I'm not even all that certain that they help.
If you think over your experiences in talking about longevity science with people, you're probably in just the same boat as me: most of the folk you'll meet don't believe that near-term progress is possible, don't like to think about aging and death anyway, and are locked into a view of their own lives that has them progressing and ending just like those of their grandparents. There is no vision, they learned the shape of the box they will live in while they were young and in school, and have little interest in change. In this, your friends and acquaintances are not at all different from any given selection of high net worth individuals.
So why be disappointed that those high net worth individuals are just as unlikely to help of their own accord, or understand the possible future of rejuvenation biotechnology? Wealth is not magic gold and blessings from the fae; these people grew up in the same society as the rest of us, and thus are on average just as blinkered - in need of education and persuasion - when it comes to aging and longevity science.
Now with all that said, you might look at Maria Konovalenko's comments on the philanthropic works of Bill Gates:
Mr. Gates said: "No idea is too radical" in what he termed as the Grand Challenges in Global Health and the goal was to pursue paths that the National Institutes of Health and other grant makers could not. Based on these statements in the article, we can see that the money has not been spent effectively so far. As life extension specialists, gerontologist and on behalf of all humanity - we are urging you to help pursue an expansion into anti-aging research.
To the best of my knowledge, the Gates Foundation makes no significant contributions towards longevity science - which one would presume means that Bill Gates and his advisors are average, ordinary folk in that regard. Unconvinced, or it isn't even on their mental radar, or they are set comfortably into the scope of a life they believe will look like that of their grandparents. And so forth. It is a challenge: exactly the same challenge that you yourself have faced when you have trouble persuading a friend on the development of rejuvenation biotechnologies and support of the SENS Foundation.