Why do you see it as bad? It's really not. I know multiple people who did as youths (though they could be thought as the more successful end of the spectrum, they're all doing well now and were doing well then).

Not all "runaways" are homeless, though, nor are they even necessarily in a worse spot after doing so.

The idea that a person should stay with their guardians until 18 is a recent societal invention, and is probably more harmful than not.

It's harder than ever to die in America, though it's also gotten progressively harder for youth to get an independent start.

"Running away" (it's more aptly described as "leaving," running implies cowardice) in itself isn't an issue, it's just a symptom of a greater problem: guardians are frequently bad, and the infantilization of society has rapidly progressed to a ridiculous point.

This is a controversial opinion, but one that's shared by almost every close friend of mine: labor laws for adolescents (I hesitate to call them "child labor laws," because infantilizing adolescents is the thing that caused the problem to begin with) have had a disastrous effect on society.

Even in the modern day, a guardian can still rob an adolescent of their earnings in America, codified by law. By any other measure, a person who can force another to work and can take their earnings is a slavemaster.