Exactly. The whole idea of eating a molecule of duck's liver "because avians are a reservoir for influenza" is ludicrous on its face. But hey, if some idiot who read about it on FB thinks it's true and wants to spend her lunch lady pension on something that is quakery, it's a free country!
Don't want the flu? Get a flu shot, practice frequent and thorough handwashing, and keep yourself healthy with plenty of hydration and a good diet. You may still get it anyways; shit happens.
For colds, zinc tabs can often lessen the severity and duration of the bug, but don't do much for influenza. Always remember that many OTC herbal things are not regulated or even tested for efficacy so you likely may be just throwing your money away if you listen to gossip and "advice." If you are taking other meds -- prescription or OTC -- be sure to look up interactions between them and any other meds you are considering.
About zinc tabs and other OTC flu/cold remedies:
https://nccih.nih.gov/health/tips/flucold.htm