No problem! Almost didn't post the comment because I didn't want to offend. Anyway, I feel like it's probably more college education than income. For many, having a college educated partner is somewhat of a status symbol, especially regarding their family and friends. I say this because people are fine introducing you to their family and friends if you have a college education because their family and friends asking what school you went to is a relatively innocuous question, but few people will ask what you make (although they might be able to make an educated guess based on your occupation).

However, I also don't want to completely discount the role of income. College educated people generally earn more money than those who aren't college educated (this is obviously a generalization, as many plumbers, for example, make more than some college educated people). College educated people typically have higher incomes and are better able to sustain a comfortable lifestyle in this expensive area, and many will want someone to be able to at least match what they're making in order to sustain the lifestyle they're used to.