You could easily go through $90,000 these days your first year in lots of schools.
I listened to all three full interviews earlier tonight, and I had the same thought that you did: $90,000 would be $22,500 per year for four years. Most colleges today charge more than that.
But, she says she pays $20,000/year. Let's assume she's estimating, and she really pays $22,500/year. (Maybe a scholarship or financial aid is covering the rest.) She paid for the first three years, but she says she spent the rest on clothes and a trip to Europe. That means she must've spent $22,500 on clothes and a trip? Nah... that couldn't be, could it?