I worked in retail for a while, and this guy came in looking for some pants. We didn't have his size (they were a common size and sold out quickly). I called one of the other stores 10 minutes away and they had them. Offered to have them hold them for him. He refused. Offered to have them shipped to my store and he could have them the next day. Refused. Offered to special order some. Refused and left the store frustrated. Comes in 2 weeks later, we go through the exact same process again. A week later, we go through it a 3rd time. Finally, on his forth visit and still no pants, I start the same old thing we'd been doing and he cuts me off:

Guy: What the hell is wrong with you and this company? You never have my goddamn pants!

Me: Sir, I did th-

Guy: I don't give a shit what you tried to do, you should have had my pants here in the store.

Me (getting angry): I don't really know what you're wanting me to say to you right now.

Guy: Well maybe you're just stupid then.

Me: Look. I did everything I could to get your pants to you, and every time you refused. You also never called ahead to get me to hold them either. Being a dick to me isn't going to make those pants magically appear on my shelf (manager at this point has overheard the conversation). If you're going to talk to me like this then I'm going to just walk away.

Guy: I wanna speak to your manager.

Manager: That's me. And you can get the fuck out of my store. You aren't going to talk to my employees like that. Get out.

Guy walks out in a rage, then proceeds to call another store and demand to speak to the owner of the company. Owner calls him an annoying asshole and bans him.

Fuck people like that. On what planet does being an abusive asshole make me want to help you more?