I can't speak for Kilobug, but my answers would be:
1. It depends on your values. E.g., how much do you value your own welfare compared to family, friends, co-workers, fellow citizens, and those other people? If you want to be conscious about it, you need to think about what you value and how you might have done things differently in that light.
2. I probably thought I was I a deotonologist, but if you carefully study your own and other people's decisions, the vast majority are consequentialists with values that tend to selfishness. WItness how many Americans are angry about the Central American children/teenagers trying to get into the US.
3. As others have commented, doing a full analysis is time-consuming and uncertain (hence "maximum expected utility"). Most of the time, one has to follow rules that generally (so one believes) that have good consequences. And generally, virtue and duty are good rules. But people make up all sorts of rules with little sense behind them. My grandmother thought opening an umbrella indoors was bad luck, but I am a little skeptical about that one.