In Supernatural, why do the brothers not give more people anti-possesion tattoos?

Question

The Winchester brothers in Supernatural have a tattoo design that prevents them from being possessed by demons.

Why don't they offer to tattoo or suggest people who have been possessed get this tattoo?

Answer 1

The Simple Answer:

They do not offer the tattoo to people who have been possessed because so few of them survive BEING possessed. Most people who are possessed by demons, and who cross the Winchesters, die and thus are not in need of protection in the future. The second reason is that if expelled/exorcised, most demons do not seek out a host that has been their's in the past. As in the recent episode "Repo Man" demons prey on souls vulnerable to their corruption but once they have completed that corruption, they move on and generally refuse to re-inhabit their former hosts.

A More Complicated Answer:

The anti-possession tattoo you mention appears first in the episode "Born under a Bad Sign" as a charm bracelet given to the Winchesters by Bobby Singer. It is unknown if any particular ritual is required to create the symbol or empower it to prevent possession. If it requires special rites, services or technologies to create, that may keep such charms in short supply, held only by Hunters who need them.

A year later, both Winchester brothers sport a tattoo in the episode "Jus in Bello" with the exact same anti-possession symbol. Again, we are not told if any particular rites are required, special inks or rituals necessary to empower them.

Knowing the show, we are forced to assume that while anti-possession charms are possible, making them and distributing them might draw attention to the fact that Demons are real and possession is a possibility, even if it isn't a daily threat for the average individual. You would be as likely to be demonically possessed as you are of winning a local lottery. Not likely to happen but it is possible.

Again without knowing if there is a particular rite required, or specialized "thrice blessed ink" we are forced to assume the sigil requires something special to empower it, otherwise it does not make sense to allow people who might be vulnerable to have to worry about it.

Consider the idea that Hunters and the like who go looking for trouble (i.e. demons) would and should take the precaution but telling normal people possession is possible reveals a dark side to society I would think most people would continue to prefer to ignore or to call impossible. Imagine if you woke tomorrow and discovered ALL of the monsters from myth were not only real but fed upon human misery and suffering and you couldn't see them or stop them without special technology/rites, people and society would suffer terribly from this knowledge, OR they would simply disbelieve in the possibility altogether. Denial is a powerful tool.

Answer 2

Although I don't disagree with Thaddeus Howze's answer, I'll offer one that is a bit more psychological - in general, the Hunters (and, of course, Slayers) tend to be more reactive than proactive. They're always responding to incoming attacks - trying to kill the newly-discovered enemies, help people in immediate danger, or just survive, and don't typically have the time (or desire) to do long-range planning, or any sort of strategic thinking.

As the old quote goes:

It's hard to remember that your initial mission was to drain the swamp when you're up to your ass in alligators.

Nor did the Winchesters even have an initial mission, they're basically making it up as they go along.

Answer 3

This is more of a theory than an accepted fact, but if many people know about demons, and all sorts of craziness, the hunters might be discovered and be expelled by religious people, sort of like a crusade.