That they do. Granted, a lot of them can be avoided by installing a case and/or screen protector. It's kind of up to you for what route you want to go.
Google
has a nice chart detailing some of the costs and rules associated with both Nexus Protect (for devices purchased from the Google Store) and Project Fi device protection (for devices purchased from Fi). They're similar, but not quite the same:
View attachment 99709
I've got a pretty good history of not destroying devices, so I didn't opt for insurance on my 6P. I
did get insurance for the wife's 5X as she tends to be a bit rougher on her devices. Either route is valid; it's just up to you.