I agree, we tend to instinctively rely on virtue ethics. And this means that we are not psychopaths.
Our apparent reliance on virtue ethics is a result of the classical conditioning of 'good' and 'bad' that has been drilled into us since birth. "Bad Timmy! Stealing candy from the store is WONG!" is very negative reinforcement for a behavior.
If we could truly abandon our trained value system for pure consequentialism, then we would all be really good at running companies. But most people are not psychopaths, and more importantly most people do not enjoy spending time with psychopaths. So for the goal of sharing effective social interaction, it is probably for the best that we hold onto instictive virtue ethics.
Now could we change this in our children with a different style of training? "Bad Timmy! Stealing candy breaks down the implicit trust that allows our economy to operate at impressive levels of efficiency!"
Disclaimer: I am not a philosopher, so this post will likely seem amateurish to the subject matter experts.
LW is big on consequentialism, utilitarianism and other quantifiable ethics one can potentially program into a computer to make it provably friendly. However, I posit that most of us intuitively use virtue ethics, and not deontology or consequentialism. In other words, when judging one's actions we intuitively value the person's motivations over the rules they follow or the consequences of said actions. We may reevaluate our judgment later, based on laws and/or actual or expected usefulness, but the initial impulse still remains, even if overridden. To quote Casimir de Montrond, "Mistrust first impulses; they are nearly always good" (the quote is usually misattributed to Talleyrand).
Some examples:
I am not sure how to classify religious fanaticism (or other bigotry), but it seems to require a heavy dose of virtue ethics (feeling righteous), in addition to following the (deontological) tenets of whichever belief, with some consequentialism (for the greater good) mixed in.
When I try to introspect my own moral decisions (like whether to tell the truth, or to cheat on a test, or to drive over the speed limit), I can usually find a grain of virtue ethics inside. It might be followed or overridden, sometimes habitually, but it is always there. Can you?