most billionaires don't have a billion dollars

billionaires own companies

the companies mostly don't have dollars

the companies do have real assets (land, equipment, inventory)

if you want to steal the real assets and achieve some immediate benefit from them, you'd have to sell them

which you can't do because (again) most billionaires don't have a billion dollars

so you can kill the golden goose if you'd like

but you can't eat it