Not myself personally, but my old boss when I worked part time at a newsy/offy during college.
Boss walks into work, gets asked by a charv to "get uz sum cans mista!" literally outside the shop.
He says "Aye, no worries", takes a fiver off this kid.
Comes into the shop, says alreet, pops to the till buys the cans and takes them outside for the kid.
Presents the kid 2 cans of Panda Shandy. Kid was like "Nar man I wanted Fostaz". Boss looks at him, and says, "well you shouldve been clearer then. Now, this is my shop, I'm the owner, I'm keeping your money, now f*** off!"
I was in stitches watching from the till.