This sounds like a silly question, but I've heard some very strong opinions about this, so I find this intriguing.
A hot dog is a type of sausage (at least according to Merriam-Webster, Wikipedia, and Encyclopedia Britannica), but I find that very few friends and coworkers agree with this, and they go so far as to say that a hot dog isn't a sausage at all. It seems that there is a perception that goes along with the term "sausage" that people refuse to associate with the term "hot dog," even though the former is a generic term for the latter.
I noticed the strength of this perception when watching an episode of American Idol last year. When Jacob says, "A hot dog is a type of sausage," not only did the others disagree, but so did people on Twitter. Enough people tweeted in disagreement with his statement that "sausage" became a trending topic for a few hours. It seems odd to me that there would be that much resentment to his statement, since it was trivial. And technically, he was correct.
I'm curious to know if this is a localized perception or if this extends to outside the U.S. as well. Am I correct in believing that a hot dog is a type of sausage and that it's not widely accepted to refer to it as such in the U.S.? If so, is this unusual perception (that a word is acceptable as a definition but taboo as a substitution) confined to the U.S., or is this sentiment common in other countries as well?