"when the top 20% are taking over 80% of the money" Who exactly are the rich "taking" money from in general? Creating wealth is not a zero-sum game. If you insert the word "earning" in the above phrase, the argument you present loses some luster.
Weirdly the answer is always "make those who contribute the most contribute more" and not "make some of the rest pull their weight".
If my company paid me, they are poorer by $1.
If the government paid me, the aggregate citizenry is poorer by $1.
If the government printed it, the total value of US dollars in circulation has decreased by $1.
Technically, activities like mining precious metals or gems could count as creating wealth, but obviously basing an economy on an arbitrarily-priced material as silver or gold is a bad idea. Anybody who believes gold isn't a fiat currency is mad.
The most successful way that governments seem to have found to tax the wealthy is inflation, which is a "tax" on liquid currency. But there's ways for the wealthy to avoid inflation which aren't available to the working class, such as buying various foreign currencies. A direct tax, rather than "stealth" taxes, is a healthier and more sustainable choice.
Gold is not wealth. It is only because it can be exchanged for a good or service that can be consumed that it has any value.
And where is it written that the "working class" aren't allowed to buy foreign currencies? Given that I'll be flying out of the US tomorrow on holiday I was hoping I'd be able to buy some foreign currencies at the airport...
Yes. But presumably when you earned that dollar you somehow contributed to making something that somebody wants. Now that thing is slightly more common, so it should be slightly easier to obtain than it was. Thus you've given a tiny little bit of value to everybody who participates in the same economy that you do. When millions of people do this we get modern civilization.