Even if they are (which is apparently disputed), pointing out that someone is using a fallacy does not make them automatically wrong. Next time, you should try saying something more substantive than "Fallacy!"
Fallacy means faulty reasoning, not a false statement. It is possible to use faulty reasoning to arrive at a correct statement. For example, "The sun rises each day, because if it didn't then everyone would die." That's the fallacy of an appeal to consequences, yet the conclusion (the sun rises each day) is correct.
Furthermore there are other forms of reasoning than pure deduction. If you allow probabilistic inference, which is how humans generally operate intuitively, many deductive fallacies turn into probabilistic theorems.