I like gas stations audits a lot. However, just for the record, you don't
always people fall over themselves to cooperate. So far, and I've only been doing this a few months, I've encountered two varieties of resistance.
1: New employees who never heard of such a thing, and beg you to come back when the manager is there. So far, the closest I've come to having a refused audit was the young woman, very polite and conscientious, who phoned her manager and read the letter of authorization to her. Then she spent the rest of the audit time apologizing to me, every time I came back in the store. (And I kept telling her that she'd done exactly the right thing.)
2: This one is a story that hasn't finished yet. I had to return to a place to grab a photo that I had missed. As I was strolling away, all photos safely tucked into my camera, a voice called to me. I turned around, and met the owner. The owner, though he repeated over and over that I should not take offense, because he understood that I was just doing my job, had a message for me to pass on to [name of large oil company deleted]. I was to tell [name of large oil company deleted] that they can go to hell. The reason that the story has not finished yet is that I had already signed up to do it, next rotation time. I'm going to be asking for some advice in another month or so.