Entrepreneurship and MBA

The title of this post was the title of a Group Discussion that i attended at NITIE mumbai for admission into their PGDIM program. As always the discussion was all about people leveraging the knowledge that they gain while doing a Management course and later How it can be leveraged to start one's own business. Now when i have made it to a good B School, this question still haunts me. What is the reason that still most of the Entrepreneurs come from NON MBA background and on the other hand most of the MBAs dont take the Entrepreneurship way. Some of the reasons that i could think of are –
Entrepreneurship takes a lot of efforts from the professional as well as the personal front. Why anybody having a cool PGDM degree from a reputed college will take all these pains.
Gains are not certain. You join a company, you are assured to get a certain amount of salary. But as you start a venture, In the first few years, the probability is that you might not even make something out of it, leave alone the question of earning what you might have in a Job with a Hotshot company.
And many more….
But one more thing that I have observed after entering a B School could be one more reason why people from B Schools are generally reluctant to go for Entrepreneurship. It is their habit of “Always winning”. The profile of a typical B School graduate almost always has excellent academics into it (and now after the Prometric goof up of CAT2009, B Schools have given more weightage to the academics part). Result is that we have a class where everyone is university topper, Board topper or at least school topper (In worst case). When these people come together and appear in a test , it’s very interesting to see how people get frustrated after getting 0.25 marks below their neighbor (Not to mention that they don’t care about what they learn , forget about applying it). Can we expect such people to look beyond the horizon of 2-3 years and try to get the knowledge that would be helpful in the long run?