Stretching off topic here, but are you sure it's not because when you're sitting in an office chair doing "office work" you're naturally moving around more, whereas when flying/racing/surfing you're generally quite motionless?

I'm sure an aeron would be more comfortable than what I normally use as "office chairs" (every chair I've had at my computer for the past 20 years has been under $100 and usually after a few months the padding wears out such that my ass bones are hitting a hard surface) but still...a racing seat just wraps me in support and spreads my weight much better. I could stand to lose a few pounds, but I'm not that heavy (~ 180-185)