Nobody (but some of the goalies) work helmets or masks.
It was a much more wide-open game without every potential good play getting waved offsides.
Fights. Yes, there were the fights.

Crowds. Yes, they had crowds.
I think it’s true that even though the Celtics were winning all those titles in the 60s, the Bruins were still way more popular in Boston than the Celtics.
The NHL that featured fewer helmets and more fights was the more polite NHL. Nowadays, the players wear suits of armour and the head and back and neck injuries have been at an appallingly bad rate for the last generation or so. You might have had nasty incidents like the stickfights between Ted Green and Wayne Maki or Larry Zeidel and Eddie Shack, but at least then players fought and died by the sword for themselves.