Laws of course are different in every state, it might be wise to check the local laws in your area. I would also say don't start turning a blind eye to things like that, and keep listing those things to your customers.
My personal rules are:
If I have to touch it, I fix it.
If I have to fix it, someone pays for me to fix it. (Unless it to minor to bill)
Always point things out, half the time they just say go ahead.
If its a safety or fire hazard, refuse to work on it until its fixed.
Just had a job taken over from some un-licensed hack who put up a 200a service with no ground at all, refused to work on it until it was properly grounded. (By me, or someone else, I don't care.) Slapped a temp ground on it, and got the rods ready. Got the biz end out of the way with the people paying the bill and started pounding.
