As mentioned upstream, it's all about ROI and reach. One of the issues here is, let's be honest, the TV product stinks. I think every person here gave NHRA a pass the first year of the in-house production but the show has not improved. Sure there are butts in the seats at the event, but the bigger reach is TV and print.
The other issue, and this is purely my opinion, is that the teams are in competition with the organization itself. If your marketing department is given a budget, looking for the most "mentions" are you going to sponsor a driver/team or are you going to sponsor the organization as an "official product" or even a national event that gets mentioned after every commercial break? It's a no-brainer. Let's look at the 2019 schedule and here are all of the sponsors that sponsor an event (or "present" an event) but are not a full-time major sponsor of a pro team:
Protecttheharvest.com
Denso Spark Plugs
NGK Spark Plugs
Arby's
Menards
Pennzoil
AAA Insurance (this is different from AAA of southern California - JFR)
NHRA "Official Product" sponsors:
Ellis Events
Honda
Larsens, Inc.
Lucas Oil
Main Gate
Pegasus Trailers
PowerAde
Sioux City Truck and Trailer
Sunoco
Toyota
Advertising Edge
Allegiant
Amkus
Blue Def
bluemedia
Buffalo Turbine
Dasani
Now, I'm not trying to call out or sound anti NHRA - I realize they need to stay in business as well. I'm simply pointing out that there is competition out there from within the "community" where companies need to determine their best bang for the buck. When faced with constant exposure in the form of commercial lead-ins, or branded NHRA assets or the "hope" that the team you sponsors gets some TV time, the answer is clear. I thought at one time NHRA's position was that companies had to be a primary sponsor of a team to also sponsor events, but that could have just been an unwritten rule or straight up internet fodder.
Feel free to keep me honest, again not meant to come across as bashing, just my personal observation on the competition that exists for the almighty dollar.