Unless a startup's highly technical, I wouldn't solely equate higher education with success - more than anything it's the behavioural skills of entrepreneurism, resilience, persuasion and street smarts that will help set you apart (unfortunately these skills are not focused on enough in formal education, IMO). It's important to know the ecosystem of the area you're going into - where the needs are, who the customers are, what the value chain looks like etc, and typically this would best be gained by work experience rather than theory.
There's many examples of successful people who never completed or went to college: e.g. Richard Branson, Henry Ford, David Ogilvy, Pete Cashmore, Walt Disney etc et al. Richard Branson once noted that the first three months of running a business teaches you more than three years at business school.
So it's not to say higher education isn't valuable, but 'learning' isn't confined to the classroom and practice oft trumps theory :)