Maybe because Apple makes it rain? Levinson, as the former Chairman and CEO of Genentech probably isn't worrying about where his next meal will come from, but all things being equal, Apple's options have generally outperformed Google'ssignificantly. In 2008 alone, he earned three times as much (over $500,000 more) from Apple as Google.
Also, as Eric Schmidt can tell you (and filed under "All other compensation" above), Apple's compensation with MacBooks and iPhones beats Google's.
