How did Mars become a NASCAR sponsor?

Answer 1

They went to NASCAR and paid them a huge amount of money.

NASCAR looks at three things when they evaluate a potential new "official product of NASCAR" sponsor: the product's reputation, whether NASCAR fans use the product and whether the sponsor can afford to pay the fees.

Reputation is all important. It has to be a product that won't cause any embarrassment, so you'll never see something like an "official condom of NASCAR."

Usage is another very important one. The product should be usable by both men and women, and within reason by both adults and children (obviously children aren't supposed to use beer, but there is an official beer of NASCAR and that's okay), and be affordable to all. You will probably never see an "official cosmetics of NASCAR" even though a lot of women watch NASCAR and would buy it, because guys generally don't wear makeup. Similarly, because Rolexes are not affordable to most people you probably won't see Rolex become the official watch of NASCAR.

The part about the fees is self explanatory.