The line between what computing should be done on what device is blurry in both directions -- it's not just "people do personal computing on corporate devices". It'd be a bit strange to hear a boss tell me to never browse Amazon or Hacker News during lunch.
I think it's wise to assume corporate-owned devices are just that: 0wned by corporations.
I use my work laptop all the time for a variety of things, but I do so under the assumption that the company may be snooping on me. (No idea if they are or not.)
Exactly. It's a work machine, used for doing work. I don't do private/personal/secure things on it, as it's not my personal computer. Browsing HN or w/e isn't really a private activity, so I don't mind it being snooped.