they were built using the system The system was built for us all to use. You could argue that they owe a moral debt to the rest of us ("give back"), but they

they were built using the system The system was built for us all to use. You could argue that they owe a moral debt to the rest of us ("give back"), but they are filling that in the form charitable works. Much like how I chose to give back with volunteer works, instead of just paying more taxes. I don't think you can claim the rest of us actually have license to their gains, just because they built their empire on top of the very same system the rest of us are also leveraging. Unless you want to claim everyone has license to all your gains too. Besides, the reason we build roads and such is because we benefit from the thriving economy that is built on top of them. It's not just about "I want a road for me to drive on". We build them to be used, and to reap the greater social benefit of their use. Now, if Mr. Billionaire was squandering the system for personal gain (example: horribly inefficient bitcoin mining with CPUs when the government is paying the electricity) that would be a different story.