I don't know why the company you work for doesn't do it. In the place where I live (Europe), it is fairly common for medium and large companies - my salary is updated every year to reflect inflation. This is independent from pay rises and is happening automatically to all employees. The places where it usually doesn't happen is the smallest companies like startups and mom-and-pops where every penny counts.
In my experience they are slightly lower than inflation but high enough to make people more or less happy. In any case, the expectations this year are extreme, so it will be interesting to see how they handle it this time (usually the adjustments are in March and we receive the compensation for January and February, too). It's not written in my contract but is a part of company policy as a means to minimize turnover.
I don't know why the company you work for doesn't do it. In the place where I live (Europe), it is fairly common for medium and large companies - my salary is updated every year to reflect inflation. This is independent from pay rises and is happening automatically to all employees. The places where it usually doesn't happen is the smallest companies like startups and mom-and-pops where every penny counts.