There's also a class issue at play. If it can only be an unpaid hobby, then only people with the time to dedicate to it (in lieu of a second paying gig) and the disposable income to buy the necessary equipment (financed entirely by their paid job) are able to participate. For example, I work with people who are also working artists. They use the income from selling their art from their hobby to pay for those materials. It's not enough to live off, so it's not their primary income, but they wouldn't be able to participate in their hobby at the level they currently are if they weren't able to sell their work. Allowing people to profit from their labor makes these spaces more inclusive and diverse.

You can! You just need a vinegar mother! I've not done it myself, but the way I understand it you can transfer the mother once the vinegar is to your liking, then on to the next one.

It's the same in that most fruits and vegetables you can buy at the store have been bred for quantity and shipping. Home gardeners can grow varieties that are bred for flavor. So my Nebraska Wedding Tomatoes may not survive a trip across the country with UPS, but they taste amazing. And my Double Gold raspberries don't produce bushels, but they're the best I've ever eaten. I do think I'm probably saving money growing garlic. Very low maintenance plant, and I grow enough to save what I need to plant for the next year. So some crops are pretty cost effective, but some are really for the flavor.