You've never lived in a state where your car insurance premium depends on your credit score, have you. I think you understand perfectly well the problems identity theft can cause, but you're just being intentionally obtuse.
> It's unclear to me... what a thief can do.
Um... well... how about anything you can do with your identity, except it's someone else? Do you really not understand why that's a bad thing?
I used to work at a bank service center. It was a cube farm filled with mostly 30 to 60-year-old women. There was occasional chatter, but it was so perfectly quiet all the time. And that's with people talking to bankers on phones.
Now I work with a bunch of 20 and 30-something men and it's like I'm back in college. Sorry, but I don't needn't to hear you not be able to control the volume of your voice for two hours on Google Hangouts. Sorry, I don't need to hear you sing to yourself while I try to desperately glue back together the thoughts in my head after you shattered them with your noise.
It's not about wringing every last drop of productivity out for your employer, it's about getting anything productive done at all. And I don't think it's asking too much for a quiet, peaceful office environment to be the default. If you want to screw around and talk at a volume that is inappropriately high, take it to the pub.