$250k is not the same in, for example, California and Iowa. If your family income is $250k in cities like San Francisco or New York, that definitely doesn't put you in 95-percentile.
San Francisco incomes statistics are undoubtedly skewed by stock option cash-outs that are one time (or at least relatively rare) events. So if you have a 250k/yr salary you might not be in the top 5% for any given year, but I bet you're in the top 5% for, say, any given 5 year period.
Not to mention that the top 5% by salary have other forms of compensation not included in the analysis, like stock options.
$250k in NYC and San Francisco does NOT offer an "upper-class" quality of life.
Really depends on what you call an "upper-class" quality of life.
A penthouse with a view of the park and the finest dining isn't affordable on 250K.
A house in a great neighborhood (unless you insist on sticking to Manhattan), private school for the kids and not worrying about most financial decisions is quite affordable on 250K even in NYC.