I was under the impression the airline can only book as many flights into/out of an airport as the airport claims they can handle. Note that weather delays can be caused by the point of departure of the inbound aircraft or points in between. My flight to BOS 2-3 weeks ago was delayed over an hour due to weather even though BOS itself was fine because bad weather in between forced us to take a wide divert. A passenger in BOS waiting for that aircraft would have experienced the same issue you are complaining about and if my flight had been at the end of the day, the connecting flight probably would have been cancelled.