We have, as stated above, a natural predisposition for the dark side of life. I would say that we tend to be more curious than most, so we seek out for the mysteries, we are attracted by them, for what is left out, for what is left in the "dark".
Correct. By the time someone decides to explore the LHP, he will have lived for quite some years, so the "nice" things are not anathema, but they are just so.. KNOWN. Which, at times, translates into "boring".
only those who look out for what is different will actually come to us
Strike - it serves as a natural "filter" which will keep the "sheeple" away.
Another point is: why would someone walk the LHP? I mean, why not just being happy with the off-the-shelf-life of "my career, my car, my house, my wife, my children and my dog" (in that order, of course)? It is seldom enough that someone will ask questions like "what am I? why am I here?", and most of those who do are rather interested in not asking, so they choose some cheap off-the-shelf-belief which will remedy the doubt.
One of the reasons is that such a person might have come into contact with the darker sides of life which can be a shaking experience. Shaking in the sense of making someone understand how fragile and temporary existence actually is.
So it is natural to ask "my last shirt won't have pockets, so what is the worth of money or a career, in the end?". Thoughts like "how do I want to look back on my life upon my last breath?" can arise quite naturally.
In fact, LHP of course includes "dark" practices, just read about the Aghora folks. Yes, they have sex amidst of corpses. That's what society will notice because its shocking. That's what lurid newspaper will feature. You see, nobody will write about the other nights where the Aghora couple just slept at home. Everybody does it, so nobody will notice this part of the LHP; it stays invisible.
What I mean is: while the LHP also aims at including the heterogeneous part of its surrounding culture, it cannot be reduced to that part. The LHP aims for completeness. At including the light side and the dark one.