But in your area, where coke means almost anything fizzy, then you would be dumb to expect a Coca Cola.


I respectably disagree. Trademark and fraud laws being what they are, if I ask for a coke, then I expect to be informed if they don't have it and give me something else instead. If I am not, then the vendor is commiting fraud. Regardless of whether I really wanted coke, or some other fizzy drink.
Can you imagine what would happen if this abuse of trademarks was extended to other items in estores?
How pissed would you be if you had ordered an 'empeg' and got sent a neo?