Most large counties do this

[LetMyPeopleVote]

Up until 2014, my county had separate primaries and runoffs but that stopped when we went to county wide voting. As a favor to the local election administrator, I was the GOP precinct judge because otherwise my youngest child would have to be the judge for both primaries. I was amused when republicans insisted on voting with their gun licenses even though that slowed up the line (it was faster and easier to check in a drivers license). I like countywide voting.