yes you are right I mispoke, I meant to say that the alignment numbers should not change because you are changing tires.
But yes one set of tires will affect the handling vs. another set entirely. Going from Conti Touring tires to streetable R-compounds was a great example.
and yes the manufacturers aren't stupid. They know every batch of tires of the same exact tire aren't always the same. Even motorsports teams fail to catch a bad batch until the driver is out on the track so I wouldn't doubt that a discount broker like Tire Rack would even bother checking. But if you have the time they will get it right eventually. To some their time is less valuable then the money they may save which can be a whole lot with $250 tires (EACH!) now the norm on high end sports cars.
BTW, my preferred bicycle tires are now $50 each.
Our dependence on oill...