re: Why did CBS pay more money for second tier Big 10 games over SEC first tier games?

The Rust belt TV markets care mainly about the NFL, not so much college. Also, those markets are struggling to grow (or even shrinking slowly). That’s why the Big 10 has expanded way outside of their footprint. Of course, the northeast and Los Angeles are not where the growth is either. The southeast and southwest are where all the growth is happening.