When i was growing up in Idaho, we had catnip out in the back yard. it was a perennial, or at least it re-seeded itself, because it came back every year, and it seemed like it also was spreading. We usually kept it pulled up around the edges to keep it from taking over the back yard. Our cats liked it, but they didn't actually eat a lot of it. I suppose that they probably had it there and could eat it any time they wanted some, so maybe it was not a big deal to our cats.
I read that it is part of the mint family, and that catnip tea is supposed to be good for you. I have tried it in tea, but I didn't really like the taste of it. it was like a really strong and odd-tasting mint.
One place where i lived, there was a lady that brought catnip in little bags to the farmer market, and she always seemed to be selling it, so i guess other people found it ok to make tea, or whatever they did with it.