Adult industry rules are perfect!

Almost everyone can earn some bucks in this industry. If a new guy comes and asks for advice how to earn some money, you just tell him to go posting galleries/freesites or to build a few TGPs. That won't make that guy rich, but the fact is that the rules of adult industry lets eveyone to come in freely and to take a piece of the pie.

Casinos have also something similar - free lotos. It's quite easy to build them but I'm not sure who is gonna to send you traffic for free.

The rest of mainstream is cruel.