I don't think anyone says that really poor people are caused by the existence of really rich people. The argument, as I understand it, is that spreading the wealth of billionaires around would mean fewer really poor people.
The distribution will go into services that compound the 5k-10k across society, not to individuals.
Education returns the investment to a nation at around 9%/year. Transportation infrastructure (especially if it's not only for roads in dense urban centres) also has a decent ROI. Investment in science, fundamental research that most private entities don't have the risk appetite for, has a massive ROI for a nation over time.
Providing public services and safety nets for a society also free up humans to take risks such as starting businesses, if you know you will be able to survive with dignity even if it all crashes and burns you are more inclined to try out that business idea instead of being stuck at a bad job. It makes bad jobs also more unattractive, requiring better salaries which reduces the gap between the haves and have-nots, this lowers crime, increases social cohesion, etc.
What exactly is the benefit for society of not taxing wealthy people out of 2% of their wealth? They mostly don't use that wealth to invest in risky ventures, they rely on banks for that.
How about the top 10,000? How about any wealth you personally have? At what point does it stop being OK for you to take people's wealth? When someone becomes a billionaire?
This reminds me of when Bernie Sanders was asked why it's OK for him to be a millionaire and he said something akin to "If you write a popular book like I did, you can be a millionaire too." Well maybe if you reinvent electric cars and space travel or build a company that ships you almost anything you can think of within 2 days then you can be a billionaire.
I agree we can/should decide collectively. But when the vast majority of Americans have a place to live, air conditioning and heat, a refrigerator, enough to eat, etc. it's hard not to say that they're comfortable. As for fulfilling, that's describing a utopia.
I recognize there are still people who are food insecure, and I think it's an abomination how people are suffering (many poor rural black people in the south don't even have access to basic plumbing and end up with diseases like hookworm), but making wealthy people into a boogeyman just seems like an emotional argument so much of the time.
