It's a thing you consider in design and for most applications, +/- 50 ppm is more than enough. There's rarely if ever an attempt to tweak the crystal frequency with a preset capacitor. Who cares if a washing machine's final spin nominally set to 180 seconds, takes 178 seconds or 182 seconds? A cheap crystal would be well within that anyway. Cost may be a factor and you can cheap out by using a ceramic resonator, or the RC oscillator option some µcontrollers have, which have looser tolerances than a cheap crystal or crystal oscillator unit.
As I recall you can buy crystals with +/- 10ppm tolerance or there are 32 kHz watch crystals which have close tolerances.
There are tricks such as using a feedback mechanism to keep a crystal oscillating at a very low amplitude, which help with stability but basically if you have something such as a digital AWG, if a tweakable crystal won't do, you have to pay for a TCXO or an OCXO, or a double overnised OCXO, or there are better and more expensive frequency reference options. Racal frequency counters came with several frequency reference options, a TXCO, an OCXO, a superior OCXO, and an adjustable basic crystal oscillator, only good for a couple of ppm, which was aimed at customers who intended to use an external frequency reference.