"Yes, pricing is definitely a factor. But the winds have been relentless lately, 5'-6' seas in BI sound will deter a lot of boaters."
we have seen this as well over the past 20 years or so - 2 or more days of heavy wind or even heavy fog and the basin thins out quickly and stays that way until the weather breaks some. If its like 2 days a bunch of people tend to arrive later and stay later making for a mess on the latter days but if it runs longer the place stays thin for a while. This is also aggravated by the cancellation policy and tendency for a larger amount of 'unplanned' marina visitors there.
Block is a wish for good weather and play it by ear destination for most.