Vaccines for what? I wouldn't give my chicks/ hens anything they don't really need as they can build up a tolerance. Same as humans. I don't take anything unless absolutely necessary. They will build up better immune systems without vaccines.
Unfortunately. This is not true. Vaccines are great for animals (including people) as they give your immune system the "code" to beat whatever you're vaccinated against. Would you advocate not giving your pet dog a rabies vaccine? Or not giving your child a rabies vaccine after they're bitten by a rabid bat ( or if there is a chance they might be)? Dying of rabies certainly wont strengthen your immune system!
Being exposed to "germs" can strengthen your immune system- but only because it helps your body know how to beat the germ in the future. A vaccine teaches your body this just the same, and in most cases where vaccines are used, keeps you alive.
I like the idea of vaccines too, and I am an RN. I have bought some from Jeffers Supply before. I have a couple of issues though, and bought some and never gave them as I did not want my birds to be 'carriers'. It is a hard decision. Now I keep a very closed flock, but I DO hatch eggs from other breeders or get hatchery chicks and I do plan to show my birds, so all those are risks, plus it is hard to know what you drag home from the feed store or even Walmart.