But you can't do anything with that money (left in the corporation) - it eventually winds up buying things for people, or being transferred to someone's bank account, at which point it will be taxed.
You could leave it on the company's balance sheets forever, but that's pretty stupid, especially if you're trying to avoid taxes, as then you just get none of the money instead of most of it.
Why not just tax the people that make up the corporations? They have to spend 51% of their time somewhere, and all taxable stuff winds up in their hands (don't tax reinvestments), so figuring out their tax obligations is simple, relatively.