Berkshire doesn't just buy stock. It buys a controlling interest and influences the way the company is run.
VC investors tend to influence the company too.
While true, the difference between the decisions the board of a company makes and the 'investors' is pretty significant. VC investors are not there to act as a board of directors. Where as many private equity/takeovers deals usually end up replacing many people on the board and executives.
They mostly make money with the private equity business by buying businesses with high cash flow and extracting more cash from them.
Then why hasn't Coca Cola been sucked dry?
That does not describe Berkshire Hathaway at all.
Extremely unpopular fact: Berkshire has fundamentally the same business model as Bain Capital. They just do it better.
I disagree, but let's say you are right. Then that model does outperform the market, no?
It does, but how much of that comes down to lobbying. I wonder who was pressuring Obama to not approve Keystone, and who also happens to own a ton of railways that transport oil?