prosfilaes
Adventurer
Look at things like the SCA and Ren Fairs, which have been around since before WWW was a popular thing. Probably not a very good example of something spreading to the collective conscience, but it is proof that fairly new pasttimes can grow to a national scale without having to be backed by commercial organizations - and without without the internet (though I'm sure it's been quite a boost to both organizations).
Neither of which require books and specialized dice, and both of which are supported by small businesses that sell period-appropriate equipment and clothing. I can believe in a world without a huge TSR, but if D&D could not make the minimal numbers for commercial print-runs, RPGs as we know them* would not exist. Furthermore, RPGs need a critical mass to exist. Chess plays with two in under an hour. RPGs usually take four and at least four hours. If there weren't the numbers to keep a rulebook in print, I think the very existence of roleplaying groups would be in question.
* I played Primetime Adventures regularly for about a year never seeing the rulebook, so I'll concede that some form of roleplaying could be passed by word of mouth. It would bear the relation that the games mentioned in the introduction have to more professional games; it would be loose, casual and hairy.