While the Clausura final isn't a battle of grandes or a regional rivalry, there's still animosity in the past between the two finalists
In lots of countries, fans joke about results the league or TV rightsholders don't want to see from strictly a ratings-based perspective. Love them or hate them, the biggest clubs in the countries get eyeballs, drawing ratings thanks to both their huge fan bases and the people who tune in because they hate them. In Mexico, where TV corporations own some of the biggest clubs, it's even easier to figure out which teams the networks want in the marquee matchups.