prosfilaes
Adventurer
I'd venture there are more people playing Bridge than there are rpgs.
Sure. But I've heard that 40 year olds who start playing Bridge get told that it's nice to see some young people pick up the game.
Regardless, word of mouth is how the hobby got started, not fancy product on the shelves. It will continue that way if the industry goes belly up. I'm not suggesting it's in any danger of doing that anytime soon, but the dirty little secret is that the hobby doesn't need the industry. It never did.
On one hand, I think you're wrong; if there aren't new books, then there won't be new people, and even the old people will get tired of working with faded photocopies of the same old, same old, and drift off to a hobby where every conversation with friends doesn't go "D&D? I thought they stopped making that?" "Well, they did, but..."
On the flipside, the industry is not separate from the hobby. If the industry doesn't exist any more, then it's because there's not enough people were buying material; and given the tiny (even negative) margins and the part-time hours some RPG companies run on, that's damming. If there's no industry left, it's because there's no hobby left to feed it.