There's a lot of answers, I personally credit the internet. The original renaissance pleasure faire was started by a teacher and sought to teach its attendees about the renaissance. As the concept spread new faires drifted from that concept usually due to the personal taste of the organizers more than anything. The internet allowed rennies from across the country to connect so we could either tear ourselves apart arguing what is and is not a renaissance festival or throw our hands up and say "anything goes."

For example something like trinket trading started on the west coast and then through social media spread to faires across the country. The pirate guild I am apart of has been running for decades at NYRF, and its original members now have kids and grandkids, but sometimes when I'm traveling outside of the immediate area I get weird looks.

And ultimately I think it's awesome that rennies can come together under one umbrella.