"...I need only one. Still, he brought me two."

Sounds to me like he's either not very bright or has a hearing disability.

"he was the manager."

And, yet, someone thought that this person who is incapable of hearing/understanding your request was promoted to manager.

Given that, I'd say you should never go back. This place has already shown that they lack the ability to select minimally competent or able managers.

In other topics... Nate, I'd like to get one of your vending machines. Delivered free to my house in Virginia. You supply the product. I keep all the money. We'll do this for 6 months. If I'm happy, then you can get paid. If I'm not happy, you can take the machine away. Please WOW me.