50% might pay income taxes.  But I would bet only 25-30% pay a significant amount of income taxes.  So yes, 7 Alaskans get a free ride on the backs of 3 Alaskans.  With sales tax, all 10 of these Alaskans have skin in the game, which is a good thing.  And likely, the 3 that make the highest income will pay more sales tax because they have more to spend.  The other thing about sales tax is that tourists will pay, which would be good for Alaska.