You need to realize that most of JMs here have graduate or highe
degrees, so do their spouses, besides Asians and Whites' incomes are already ranked higher comparing to Hispanics and Blacks on average, with this combination, JMs' expectation to a middle-comfortable-class life is a bit higher than average. :)
This topic is just to discuss how we "measure" middle-class based on our own standards, not census' numbers, so, don't take it too seriously, just for fun.