Can someone explain, regarding the "pop"/"soda" map, who calls soda "Coke"? Since when (and where) is "Coke" a generic name for a carbonated soft drink? Does this mean that grape soda is called "grape coke"?
"Coke" is generally the generic term for cola type sodas (ie, Coke, Pepsi and RC) but not sodas in general. I encountered it when I worked in food service because most places carry either Coke or Pepsi but not both and people ask for "Coke" as basically "whichever baaic cola you carry". So grape soda wouldn't be "grape coke" because grape soda isn't a cola.
"Coke" is like "band-aid" or "kleenex" in the South.
Southerners are more apt than others to use brand names for products.
It's like this:
"You wanna Coke?"
"Awrite."
"What kind?"
"You got orange or root beer?"
"Naw, just regular Coke and Sprite."
"Gimme a Sprite."
Texans refer to all pretty much all carbonated beverages as "coke", as in "Let's go get a coke". Some people say soda-water, as well.
I have a vending route (and I sell a ton of drinks). If someone asks me for a coke while I'm filling a machine, I'm always careful to ask "what kind".