We know the vast majority of people get into RPGs by being introduced to it and we know gamers ddon't do all that much to introduce others, right?
So what if game designers gave out referral bonuses like "for every person who mentions your name when they by my rpg, I'll give you some $". Maybe even put a page of referral slips in the back of each book.
Would this work?
It might a little. Mostly what you'd get, however, would be the other players in the group who wanted a copy of the game. Which would be reducing profitablility without increasing exposure. Thus for the industry it would be good; for the individual, quite likely bad.
That's just a WAG, though. I could be missing something in my snap analysis.
Mike
If you really want to sell your game, why not let the referal slips give discounts on supplements to your game instead? :)