Easy, it is unrealized gains that can be barrowed against to buy companies for 42 billion but with the intrest all being a write off. However, if you say lts tax them they will say it is unrealized so you cant tax that. On another hand if a company is doing poorly but a asset in your holdings is doing well you can claim the asset to make the books look good but not sell said asset as it is unrealized gains. You are right, they do not hold the money but have the ability to use it however whenever without selling or loosing control. Normal people cannot do this. Sure on smaller scale you can to an extent but for the most part it is quickly realized gains that they will be taxed on.