In their rejection, Busch tried to make their case to the shareholders regarding how they were going to increase savings and cut costs. Unfortunately for Anheuser-Busch, their stock that has been underperforming compared to its peers and it's looking increasingly bleak for the domestic mass-market brewing business they're so heavily invested in. They're still seeing growth but if you could snag 12% over market value for that stock, you'd be foolish not to take the money and run. There are better places to invest right now. Given that loyalty isn't a quality shareholders tend to have a lot of, I can't imagine InBev failing here.
UPDATE: Wow, things are getting fun faster than I thought. According to a few analysts, InBev may go back to the board with a much higher offer. So much for hostile. The board will have to cave at an offer of 10x what Anheuser-Busch makes in a year. Even if they had the shareholder support to turn that down, it would still be bad for Busch. InBev would just buy or partner with one of their rivals at that point.
UPDATE 2: Rush Limbaugh has an incredible quote regarding the takeover:
Yes, Mr. Snerdley, a question from the program observer. That's right, the Belgians have no interest in fighting terrorism. They've got their priorities. They'll fight for beer. If you were in Brussels, Belgium, what would you do, fight terrorism or fight for beer? And so yes, the Belgians are going to go to the mat here for Anheuser-Busch...