Toe is going to affect tire wear more than camber. Most modern cars with sporty intentions are designed for negative camber in the rear. You could dial it out, but in turn you will be sacrificing corner traction. The payoff will most likely not be worth it, unless you take your corners like you're driving a 1980's Suburban, then it might be worth it to dial your camber closer to 0. Or trade in your Z
But from the posts I've read on here and personal experience, you can expect 15-20k between (non-stock) tires depending on your driving habits and the tread rating. It can be pricey, but you're also not driving a Camry lol.