* Comfortable retirement - 401k contributions. Yes America has social security but it's not a ton of money compared to other national pensions and if you're young you worry about it not being around at all by the time you need it.
* Unemployment - You should probably have ~6 months living expenses saved up, if not a year, in case you get laid off. U.S. unemployment benefits are fairly marginal (~700 per month cap when I used them in 2002, which you owe tax on), especially compared to Germany/France.
* Life insurance - If you have kids and/or a non working spouse you need to make sure they will be OK if you die, since we have such a weak social safety net.
* Education for your kids - 529 and educational IRA plans allow people to save for our increasingly expensive higher education even before the child is born (I-Bonds can be used this way). Cuts to public colleges have been harsh this year so don't think those will save you.
Yes many Americans blow their salaries on dumb consumerist crap, and tend to overinvest in things like real estate. But even the prudent ones will be trying to jack up their salaries because there are SO many things you are supposed to save for to be considered a responsible American adult.