You're right, we should have to do this stuff, but it becomes part of our job and we must do it.
In the eyes of the customer, whether that be a homeowner, GC, building engineer, retail manager, or whatever, our job is to produce an end result. To the extent that we are able to anticipate problems, the better we cal pull off that end result. This is the difference between an installer and a good tradesman. The ability to anticipate problems and conflicts before they occur is what makes you look good in the end.
There are the odd times where you can anticipate problems, and you let them happen anyhow for specific reasons, but that is the exception rather than the rule. If you enjoy working for GC's, one of your goals should be some manner of repeat business. The less "problems" a GC has from your, whether you caused them or not, the greater your chances of working for him again.
In the case of the OP, we're talking about an extreme amount of buried items, and I sure as shooting wouldn't tolerate that either. What I am saying, though, is that having pictures, video, or having taken time to mark the floor may well have been all it takes to make you look like the real expert and not just another in a long line of guys with something to cry about.
Wiring a house is pretty simple to pull off technically. The difference between a guy who does a good job wiring a house and a guy who just wires houses often hinges on the good guy's ability to anticipate problems and conflicts and took steps to see that the don't become real problems or conflicts.