One of the basic features of language is that meanings of words change over time, including a given term retaining is original meaning but adding another one (did you think, for instance that all of the different meanings of the word "scale" were invented at the same time?). That being the case, using traditional meat terms for vegetable products that are similar to meat is perfectly legitimate.

Nobody who buys a veggie burger mistakenly thinks they are made of meat. In fact their knowledge they are not is usually a key reason they buy them