It's one thing to want to keep a tradition alive, but it's another to say those who don't use PRB aren't really hunters.
I'm all for keeping the tradition alive, and like you, I prefer the looks of side lock. An inline is too much like a modern rifle, and just doesn't hold my fancy. But I wouldn't down you for using it.
And not all of those guys are like that. There are just a few. Most will politely tell the new guy that "those" or "that" isn't discussed here.