system
Given the following post, respond as if you're commenting on Reddit:
human
What value do cryptocurrency investors add to society?

I guess same goes to stock investors as well. My idea of an economy is you produce goods/services for society and get rewarded with currency, which you can then spend on good/services that other people produce. You can only take as much value out of the economy as you put in. 

But this must not be correct because that very simplistic theory breaks down when it comes to investing. When someone makes a million dollars off dogecoin, they didn’t create a million dollars of goods/services for the economy. So why should they be able to take a million dollars of value away? All they did was hold an asset that appreciated tremendously, but where is the value created?

My knowledge of economics is very limited so any explanation of why my simple economic theory is incorrect would be appreciated.
gpt
Stock investors are investing in companies that theoretically create value. Capital is aggregated through investment to make things possible that would be otherwise impossible for most people not named Jeff Bezos or Elon Musk. They obviously hope that as their underlying firm creates more and more value that their ownership increases in value. This is a very important aspect of an advanced economy. 

Crypto “investors” on the other hand are not investing in anything of inherent or intrinsic value but rather they’re speculating that someone will pay more one day despite the underlying “asset” remaining inert and unproductive.