Should a poor student study an MBA from private B-schools like TAPMI, KJ Somaiya, GLIM, BIM, GIM, etc.?

The decision to pursue an MBA program from a private business school will depend on your responsibilities, family background, and financial strength. Apart from these, the factor that should be the most important to a poor student should be ROI. 

If you consider the average fees, the course duration, and the average package during placements, you can calculate the amount of time it will probably take to pay off your student loans. You can extend this method of evaluation to the various colleges mentioned in your question, and then pick the one with not only the best ROI, but also the least amount of time it takes for repayment.