Even in a world where the only model is commodity -> gold/money -> commodity, there will be people who will hoard a commodity to sell it when the demand is high. So, hoarding and making profits is a human nature, that just cannot be avoided.
The desire to do that is human, sure, but we can build systems to limit its impact.
We could have a negative interest rate, tax wealth rather than income, etc etc. People going to try to hoard, but you can add friction to make that harder.
That is popular thinking right now but exactly the opposite of what makes economic sense.
Taxing income is counterproductive - an economy should reward, not penalize, the creation of value, whether that is individually or in groups/companies.
But taxing wealth is even worse - savings and investment are what generates higher rates of productivity.
By far the best thing to tax is consumption. But it will always be unpopular because it just seems unfair since people must consume to survive. But it's the only truly fair tax, since it actually makes taking from the world more expensive, rather than making contributing to the world less valuable/profitable.
You can hoard services coupons aka money. Just think about being the guy on the other side. One guy accumulates 50 years of burger flipping and you are 60 years old and now owe someone 50 years of burger flipping. That money is effectively worthless its value will be reduced by inflation and no the government didn't steal 40 years of burger flipping. The simple act of 40 years of aging did that.
