The creators of one of the shows I watch on DVD -- I think it was the Simpsons -- said they'd often put in product names and hope they got positive feedback about it later.
Maybe it was Psych.
Wasn't anything they needed to clear apparently. Or anything anyone paid for. And sometimes they got a token of gratitude and sometimes they didn't.
So maybe Wawa did pay for the product placement or give permission, but hard to say.