The "is a hot dog a sandwich" and similar discussions are solved with the mighty sword of language and not some rigid taxonomy about fillings and bread.
Imagine a set of food items on a table, hot dog amongst them, but not other pseudo-sandwiches. I ask you to "Please pass me that sandwich." If there is but a moment's pause in your mind before you reach for the hot dog, even if it's as you surmise I must be speaking about the hot dog as there are no other sandwich-like items available, then it is not a sandwich.
Do you remember growing up and asking "how was it even possible that someone as monstrous as Hitler was put in power? He wasn't shy about his intents!"?