...I wonder if Monaro shocks (on Elvins car iiirc) don't have the camber adjustment the omega has. Perhaps?
For the record my Catera has Koni Sport inserts in the original strut bodies so the upper and lower knuckle holes are exactly how they would be on a stock Omega. She also has Powerflex front/horizontal bushes and new tie-rod ends. I didn't install the eccentric bolts myself so I can only attest to the results I've experienced. I don't have exact mileage numbers but the tires have lasted longer and worn more evenly after the bolts than before them. The wear is still based to the inner part of the tread but that's just the nature of our suspension.
Yes the state of the wear is due to the suspensions camber setting. The wear should be focused towards the inner edge by the time the tyre is spent ( we have a 3mm tread wear limit on the centre two thirds iirc ) but driving style affects the wear so more aggressive drivers need more camber to achieve this. Apologies if I'm quoting the rule book at you though I'm sure you know all this.
Point is the tyre wear is not to do with the bolts. The original components do not need them, or at least not to enable a setting that is otherwise out of reach, anyway.
I've not used them, as not needed, so can't dismiss them completely but, for instance, Smeagols car runs 30mm drop front suspension, stock boots, yet there is still excess camber available.
When the car came to me it was running an inch higher than stock too. Same bolts achieved the required setting.
What might be handy is the ability to turn the camber bolt with the eccentric section within moving the top of the hub in and out as required, in order to adjust the actual camber setting during set up. Although I guess the bolt length would need to be more cranked than excentric. But other than that....
...No need.

Apologies re the Monaro shocks guess. Must of been another thread I saw.