Originally Posted by Halfkiddio

Welcome to performance cars. That tire wear is normal if you're always driving it to enjoy it. Also, the OEM tires suck for wear. You need to get something like a set of Michelin PSS or PS4S to replace them when they are fully worn out.

For reference, I have had 6 sets of tires on my Z in just about two years (17 days away in fact). I don't drive the car casually very much, and usually have less than 10k miles on a set of tires by the time they are dead, with the front and rear wearing evenly.