Pet animal laws have changed a LOT in the last few decades. There are a TON more restrictions now (necessary ones) than there have ever been before. You can’t just go out and catch a native animal and make it a pet, for instance. And you need a special permit to keep most primates, like a monkey. (Although I’m not sure if this state or federal; bird laws tend to be federal because birds tend to cross state lines.)
But it doesn’t surprise me at all that as recently as 1967 those regulations weren’t in place. I worked in the pet industry for around 8 years, straddling the 80s and 90s, and just during that period the legal availability of a TON of pet species changed. We went from selling a huge range of turtles species, from all over the world, for example, for around $15 apiece, to selling just a few species for $50 to $100 apiece, due to changes in regulations governing the collection or import of reptiles. Just for one example.