People garden and gather mushrooms to feel self-reliant, like they have the skills to survive.
Gardening and mushroom hunting, however, are very different experiences. In a garden, plants present their fruits (to ensure propagation). In mushroom hunting, the species you’re looking for is hard to find; it literally hides in nature.
Mushrooms are wild and pursue an agenda different from yours; some of them can kill you. That’s why looking for mushrooms is called hunting rather than gathering or harvesting.