The big breweries are facing a lot of competition and I'm sure It worries them a bit. Lots of places in town with 24 taps only 2-3 domestic macro brews (some places no domestic macros).
My bar sells most tap beer for our sales reps accounts and only one is from a macro brewery (8 taps). At the same time domestic macro makes up probably half of our can/bottle sales.
I'd guess that Portland is an outlier with breweries all over the city and the state.