I'm going to have to disagree that you are "a paid a little less" at startups. In my experience working for a startup is a 20-30% drop in compensation.

When startups say they are near market, they mean base salaries. They neglect bonuses, stock grants, signing bonuses, stock refreshes, 401K matching. These things add up real quickly. Even worse, I've found that startup salaries usually don't grow as large companies (very few startups do equity refresh, raises, COL increases, etc.)

Compound this 30% difference over a 4 year stint and things start to look bad, esp. when you think of $1m+ home prices left in startup havens like San Francisco & New York. If the majority of startups were in affordable cities, I'd agree that the compensation difference isn't that much, but the bulk of startups are located in places where that 30% drop means a significant change in quality of life.