That's not accurate. He didn't pay for anything as he was groomed to become a senator in IL. Nothing. Michelle went to Princeton and Harvard. She was a partner in a $2.5B law firm in Chicago (where Barry also worked, not as a partner). You can go look up their real tax returns here:
LINK
In 2000-2004 they reported $275,000ish W-2 income each year, no business income.
Iy 2005 they reported $1,670,995 in income. $1.1M of that was business income.
In 2006 they reported $991,296 in income, only $506,000 of which was business.
In 2007 they reported $4,238,165 in income - $3.9M of which was business income.
In 2008 they were down to just $2.7mil income, $2.4mil of which was that business income.
What isn't reflected here are the lifestyle things that they get by being involved in all these other orgs. $275k isn't off the charts, but if you live like royalty by association you don't need the money for a damned thing. And that's what they did. They were practically poor compared to most congresscritters, that you are right about, but not regular people.