I do use butter in relation to burgers. I might use it to toast the buns, I might also use it to fry and baste the burger while it's cooking (Culver's, Home Of The Butterburger-style), I might also slap a pat on the finished burger to melt while it's resting, and on those rare occasions when I just have to have a burger and all I have in the house is lean/extra lean beef, I'll add chunks of butter to the ground beef before I patty it out.
My "hamburger sandwich" story: we were on a long drive, and the wife was nodding off (as usual) when I pointed out we'd need to stop for lunch at some point: "What do you feel like?"
"I don't care...just some kind of sandwich. A sandwich sounds good."
An hour or so later, we reached an exit with a few restaurants, and I pulled into a burger joint, then woke her up.
"Burgers?! I said I wanted a sandwich!"
"Um...a burger
is a sandwich."
"No it's not! It's a...a...burger! It's its own thing! It's
not a sandwich!"
"Two pieces of bread...a filling...I think that's what's called a sandwich."
"No! It's! Not!"
So we went inside and stepped up to the counter to order, and I kid you not, the girl taking the order said...<drumroll>...
"Hi! Thanks for choosing BurgerTown! What kind of hamburger sandwich can I get you today?"