Now why would anyone call pop Coke? Coke it the name of a specific pop, not a name for all pop! My wife went to Boston area once and ordered a pop, and they thought she was trying to order some booze!
I usually order by name of pop, but I usually rather have beer, tea (unsweetened, thank you) or water. In that order.
We native Bostonians don't know from pop. Soda, we got. We'll give you a Coke if you ask for a Coke. Want Pepsi, ask for Pepsi. But none of that stinkin' sweet tea.