In the stock market, Mr Market determines the price, which some times go crazy and the owners of businesses (ie shareholders) have no choice but to sell at basement prices. Buffett takes this opportunity to buy from these willing sellers. Well, in the first place, some of these market participants never regarded themselves as the owners of the firms which they hold stocks. They are in for the quick gamble. So Buffett gladly profits from their fear.
However, in private transactions, Buffett knows these sellers. Some of them are his friends in Omaha. He is not going to shortchange them. So the logical conclusion is that Buffett pays a reasonable price for these businesses he buys, Maybe 18x earnings. We can think of it as the sellers get 18 years of future cashflow from their business. Thereafter, the profits will be what Berkshire shareholders stand to gain from. There is bread from everybody. Nobody gets shortchanged.
To put it graphically, value investing is often viewed as buying an asset below its intrinsic value with a margin of safety (ie buy when purple line is below green line). Since Mr Market eventually prices asset correctly (albeit after a long time and only for a short while), money is to be made when value investors buy stocks way below intrinsic value and wait for it to rise back to intrinsic value.
However what Buffett does with buying good franchises would be buying an asset at its intrinsic value, at that point in time. And since it is a good franchise, its intrinsic value rises over time and way out into the future, Berkshire shareholders benefit from the exponential growth in intrinsic value. This is perhaps why he keeps talking about buying a strong franchise at a reasonable price, rather than buying a mediocre firm at bargain prices.
In every transaction, we are taught that usually there is a buyer and a seller, and there is a winner and a loser. Yet in Buffett's position, it is possible to have a transaction and yet benefits both the buyer and the seller. In my opinion, this would qualify as the acme of value investing.