Tagging like this is as old as humanity~
Older even...dogs pee on fence posts and fire hydrants for the same reason.
One thing I would add is that we're all to quick to identify the actor and the action, but they're not the same.
Tagging doesn't make the taggers idiots any more than dogs are idiots--it's just regression into very old and ingrained habit of our species.
The activity is
certainly dumb, and reprehensible.
But to judge the entire person based on one stupid act without any other information about them is not very smart, either. We all do it (me too)--there is something perversely pleasant about verbally spearing someone who does something we detest. But where it goes is not pretty. So why add to the hatred in the world--isn't there enough of that already?
If there's one thing that the Camino slowly teaches me it's tolerance and patience with the idiotic things people can do. So if it bugs you enough, take care of yourself and clean it up--but without illusions that the Camino will remain pristine after you come along.
@Rebekah Scott and The Ditch Pigs clean up tons of trash every year. And they seem to have fun doing it.
That is what it looks like to use the lessons of the Camino well.
Rant over (I'm talking to myself, by the way).
Bottom line is what you just said, Teddy:
A bit of human grit is unlikely to prevent people from coming. And if it does, maybe they're just not ready yet. No fear!