Factored into the tolerance is the temperature coefficient, because the tolerance is specified over the operating range. There are also 3 basic temperature ranges: Industrial, automotive, and military. I've used this to my advantage by spec'ing automotive capacitors when I needed tighter tolerances for my normally room temperature applications.

They also laser-trim IC's.

'Laser-trimmed resistors' will be the next selling point on a boutique guitar FX company's 57th clone of a Tubescreamer.

And before digital circuits. All I see now is 10k, 1k and 100 Ohm resistors.