DRS Your GME

Companies do not generally go public and start offering shares just for the fun of it. They need that influx of money from the initial offering for one reason or another. A company's overall margin is also generally not very large, especially compared to its market cap, which is what would need to be bought back. Amazon's profit of ~10 billion is trivial in comparison to their market cap of 1.5 trillion. Even their total annual revenue is still only about a tenth of that. They'd need to shrink by at least an order of magnitude for a buyback to even be possible, let alone plausible.

TL;DR: It is extraordinarily rare for a publicly traded company to have the cash flow necessary to consider buying itself back.