People do that anyway, just that you'll have tough luck if it comes up in an insurance case. Or worse if you are in a condo and other people suffer.

Wiring and outlets are simple enough, but you wouldn't believe peoples' capacity to botch things up. They'd connect a ground pin socket in place of non grounded one without changing the wiring, or use incorrect section wire, or with incorrect insulation type for in-wall application, or they'd replace a charred outlet without trimming the sooted part of wire. Enough nuances to avoid amateur work.