Well, I'm sure you make some "enjoy the present" vs. "enjoy the future" tradeoffs (e.g. safe sex, hopefully). This trade-off will simply be different for each person. In any case, the author wasn't very clear on this, but it's not necessary that his sister (a manager) actually worked more; plenty of programmers work a lot as well (overnight support, weekend work, "we have a deadline next month" sprints, ...).