Bad Service? Trust? What happened?

Whatever happened to the old, "you trust me and I trust you" deal? Is it gone forever? I got a lesson this weekend from a small U-haul place. The guy, who lacks any enthusiasm for the job, has me sign a contract and initial where I don't plan to take the insurance (the truck is dented all over) and to initial where I promise to fill the truck up with gas. THEN he gives me the keys. Well, I'm late and I jump in the car to go pick up my new front doors. As I look down- I see the truck isn't full. I return it an hour later and fill it to where it was. No one's there to tell, so I drop the key in the box and call up the next morning. He's already charged me 50 bucks for not filling it up. He tells me I signed it and I tell him he didn't give me the key until I did. He says, oh, I would have known. I told him where I filled it and he says, too bad. I told him, I'm not trying to scam him and describe the scary place I got gas. He says, talk to the manager tomorrow. I tell him, fine,I'll just stop payment and pay the correct amount. He didn't like that. Where could I have driven in an hour? How far? Where is the trust? Is everyone expected to lie now?