Actually, their lives are even more extravagant than that.
They hope to save $100K in another three years, after having saved for three already. So let's say $15,000 instead of $30,000. They live right by work and take the subway, so no car payments either. So, let's say $5,000 (two unlimited MetroCards for a year, plus $200+/month in cabs we'll say they forgot about) instead of $12,000.
So that's an extra $22,000 on top of the incredibly generous hypothetical budget that venkol made.