I understand what you're saying, but it's apples and oranges (see what I did there?). You're talking about onsite maintenance of enterprise computer equipment by highly trained, professional staff. And if they cause an outage it could potentially cost the client 10's or 100's of thousands of $$$.
This is a kid in a little shop at a strip mall or kiosk in the mall, doing a 5 minute battery replacement with virtually zero risk. Think changing your cordless phone battery, but with smaller parts.
I suppose if someone had bad eyesight and their hands were shaky, there's some risk. :-)