I bet that busyness of hairdressers does correlate with shifts in the economy, particularly on a local/regional level. I'd suspect that early November is a point where a lot of people put off their cuts, though, until right before Thanksgiving, or in early December so it looks good for the holidays and associated events.
I spend ~$50 with tip at my current place for a wash/cut/style, which I think is about as low as I could go in my high COL area and get a decent result. A couple of years ago I was getting my hair colored, highlighted and cut at a medium-high salon, and although it looked good it just got to be too much - $250 every six to eight weeks was just a ton of money.
I've always been kind of a cheapskate with hair styling, maybe because I grew up in a place where it was a lot cheaper, or because it's something that fades so quickly, and you have to redo often. Clothes, in comparison, you get to keep for a lot longer.