First of all, the cost to declare or register in a party in order to vote in that party's primary is nothing. So all citizens are free to vote.
Secondly, there are two major parties and it is in the interest of the state to ensure that their contests are conducted fairly. So it is your process, too, since you will be effected by the outcome of the promaries.
SD
No, actually they aren't. I'm a registered independent, and I am excluded from voting UNLESS I declare myself a member of some party, which I am not about to do---yet my tax dollars go to paying for the election in which I cannot vote.
"there are two major parties and it is in the interest of the state to ensure that their contests are conducted fairly. So it is your process, too, since you will be effected by the outcome of the promaries."
Well, you got PART of it right---I'll be affected by the outcome, but with no say in what that outcome might be.