Sponsorships really have slippery business cases.
For one, it's terribly hard to track profitability from sponsorships, which means it's hard to even pitch it unless you're already a rising star.
Secondly, depending on the level of sponsorship, it can be quite an expense. Sure it's not as pricey as sponosring a car/driver on the NASCAR circuit, but nonetheless between travel and PR it's still a large expense.
But I do think it would be nice to see someone wearing an EF shirt on ESPN2.