Two main reasons for this, as I see it (having worked in a such a setting for about a year before getting the hell out):
1 (internal reason). Large Indian offshoring companies (TCS, Infosys, Wipro, HCL et al) have a HUGE workforce, and recruit fresh engineering under-grads in massive numbers. All the bureaucracy becomes somewhat necessary in order to manage undertakings of such magnitude
2 (external reason). Work-quality-wise, there isn't much difference between contracting work out to a TCS vs Infosys vs Wipro vs whatever else - hence this immense pressure on such companies to cultivate and tout such aspects about themselves. And let's face it, when you're farming out grunt work to code-monkeys, you kind of expect a 'monkey see, monkey do' attitude..