Had a nice chat with my neighbors several years ago, right after moving into our new place....it went along the lines of "yeah, if anyone ever tries to start an HOA here it will be met with resistance...we will not be 'joining' it"....it was actually a little more colorful than that, use your imagination...
We have local code enforcement, that's more than enough! The charm (and I'm serious about that) of our neighborhood is that it's very different / eclectic, there are small houses, big houses, modern-style, older houses, nothing is cookie cutter. There's even an A-frame.