Anyone would be way more valuable to a startup after a couple of years in industry. I would say that Amazon more so than others (maybe a little biased..) because of the team structure, engineering tools and development practices.

Knowing what I know now, if I had gone to a startup straight out of college I would have been worse than useless.

At the risk of just repeating what deegles said, do startups really want the overhead of a new grad? I've met people 2-3 years out of school who can barely communicate or work in a professional environment. I can't imagine dealing with a new grad plus the faster-than-average-corporate environment of a startup.

Not as employee 1 or 2 or 3. Maybe by employee 5 or 6 you can afford 1 or so new guys. New guys are awesome, but a lot of work. Hard to justify them for a few years...