Allow me to give the exemple of meat eating for this question: In the suttas we can clearly see (many times) that eating meat is accepted in Buddhism under a few conditions. We cannot kill, ask someone to kill or hear/see the animak being killed.
In addition some meats should not me eaten (human flesh, elephants etc...), but most of the meat we eat today is clearly accepted in the suttas, still there are people that look down on you if you eat meat, mixing personal views with Buddhism.
There is a sort of "main stream" Buddhism with things clearly not coming from the suttas, in this case, should we correct them? Or should we respect other peoples view?