I think you raise a good point, and personally, i've noticed a couple of reasons for the "employee" mindset at business schools.
(1) One reason to get an MBA at all is because it provides extra job security. If you're the kind of person who wants add'l job security even though you already have a job (most MBA applicants) and even though you already have a college degree, then you're by nature quite conservative -- which may be part of the "employee" mindset you mention.
(2) Most MBA programs realize you don't really need an MBA to be a successful entrepreneur. Look at all the truly successul entreps in the US. Few of them have their MBAs. For that reason, it's actually difficult to get into MBA school with a stated goal of just doing entrepism after graduating.
(3) i-banking and consulting are popular career choices post-MBA, because not only do they pay a great deal, but they also have faster career tracks and are great for people who don't really know what they want to do. As much as I harp on people to get crisp in their career goals when applying to b school, very few actually really know what they want to do post graduation.
it's an interesting point of view that you have and smthg I've thought about a great deal as well.
hope that's helpful,
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