Interesting thought on rear camber after the 4 wheel alignment,
i have recently had mine done after the engine rebuild and rear suspension parts rebuild,
i had a full alignment on a brand new state of the art alignment machine,
very little wrong apart from tracking and rear camber,
And thats where the interest comes from, i have been told catagoricly that the is no adjustment on the rear camber, also had this confirmed by my indie, who reffered me to them, the service cost me £123 inc vat, and this was a proffesional motor sport company.
so without wanting to put a damper on your statment i think they may of been lying some what,
Unless they fitted shimms on the rear hub.
Maybe worth check to see if they did do it.
for uneven wear maybe think rear bushes shocks, and sub frame bushes