Ha! I remember not ever setting up my voicemail at one company where I was a contractor. Got a little pushback from one guy, but he liked to call when he knew you weren't in the office and leave long rambling messages. I told him it was like hes saying, hey, YOU type this email for me.

Later in my career I've deleted email accounts when they got too full. Just switched. Caused hardly a blip. I'm guessing its for much the same reason - people expect email to be largely ignored now, so its no surprise when I don't respond to some non-urgent ramble.