For the love of God you are attacking the referees because they are from Castlebar??? :o
Based on your post you are basing this call on been at a few matches and hearsay from the B games, would the B team have lost these matches by any chance?
"Been told" and "believe" really don't prove a basis for daft statements. The story is that you are listening to too much pub talk!
As the lads said the big number of refs are from Castlebar so the easiest thing to do it say they are bias towards Castlebar!
Best thing for you to do it go and do the referees course and see how you get on, or else find out why Westport has only 1 ref (that i know of at senior level).