I don't think that's the point that nuclearnice1 is making.
The focus is not on the other bidder (who may or may not have gone on to make a fortune).
The point is the seller could have gotten more than what Schulz paid for the chain. If this was a corporate m&a situation and a second bidder arose at a higher price, the board has a fiduciary duty to consider that offer.
What's more likely is that Schulz would simply have started a different chain, and we'd be talking about that company the way we do about Starbucks now.