"dude out of that 72k, you will pay about 30-35k for taxes because your position is very likely based in NY or London. Add in housing expenses and you are not left with much."
Well, I'm based in London, so it's 36400 GBP, or roughly $72000. Taxes leave that at around 29000 GBP, minus 4800 for housing and utilities, plus 1000 relocation bonus

leaving me with 18000 GBP left over.
I can easily put around 10000 aside in a high-interest account and live off the rest quite comfortably... or 8000, and live more comfortably... either way, I don't have to worry about rent after I graduate, even if I don't have a graduate job waiting for me.
I don't get bonuses, but neither do all the other interns - and besides, MS pays everyone at the same job-title equally, it's just the bonuses that each section gets that make the difference... e.g., M&A easily will double a consultants salary through bonuses.