Especially if you're going somewhere a bit "touristy"; you'll find more options for places to stay and lower prices. Plus less kids running amuck, which is always a win for me <g>.
Also, and in light of the big picture, this isn't necessarily a "win" but...it seems to me like in general, it's warmer in October than it used to be. Back in 2016, I spent a week in October in Rhode Island; the Sunday I was there, it was almost 90°. It might as well have been summer. I actually went to a beach and hung out for the afternoon--the only downside was a lot of the places at the beach that might've sold snacks or souvenirs were closed for the season. But RI is so small...I didn't have to drive more than 10 minutes to find a place open for dinner.