Ordering Magic

A couple days ago while talking to finances.

Me - "Hey, I am going to go get the food and stuff for the party. Did anyone order the items so I can get them?"
Co-worker - "I thought you were buying them."
Me - "Well the email said...and this email was from you...that you were going to."
Coworker - "No it didn't."
Me - "It didn't?"
Coworker - "No."
Me - "Ok... 'I will buy the food' must mean something different than I thought when I read your email."
Coworker - "I guess it did."
Me - "Ok whatever I will go get it."
I go to the store spend about 40 minutes picking out stuff.  I bring it to the lady behind the desk and say to charge it to my company.
Lady - "Oh, we have that. It's under so and so"

Ya, all the items... had been purchased... by that coworker.
When confronted with the items-

Coworker - "I don't know how they got ordered."
Me - "No clue... how they used your name and your personal credit card... copy that."