I don’t think that’s true, is it? I think Gondor had a small handful of kings before the line was broken and had a long string of stewards. Didn’t Isildur sail from Numenor and establish Gondor himself? So, one single king, right?

Remember, they are still pretty much children in Hobbit society. Both the Tooks and Brandeybucks hold fair bits of land, it’s just their wild kids running around giving the farmers trouble. And of course there’s never any real consequences for them beyond a slap on the wrist.