I think this piece, Admit It: You're Rich, by Megan McArdle is brilliant. Now, that may just be because I agree with her and point it out to people who complain about the rich, usually with an offer to take a check representing their net worth minus $2,000 to the Gambian embassy so they can help out the poor.
So why don't we feel like Scrooge McDuck, rolling around in all of our glorious riches? Why do we feel kinda, y'know, middle class?
Because we don't compare our personal experiences to a Tanzanian subsistence farmer who labors in the hot sun for 12 hours before repairing to his one-room abode for a meal of cornmeal porridge and cabbage. We compare ourselves to other Americans, many of whom, darn them, seem to have much more money than we do.
Envy tends towards ugly. So instead, enjoy the blessings you have, feel free to work hard to earn more, and do not begrudge others what they have.
Unless it's a sub-3 hour marathon PR.
Nah. On second thought, just go run your guts out - you're still miles ahead of the rest.