Earlier quoted context omitted.
I charge for copies of free software I wrote, an AGPLv3+ desktop application, and earn about $2k MRR from it. Most people don't care about your choice of license, they just want software that conveniently solves their problem(s). If they want to share it, that's fine. They're giving it to people who wouldn't have bought it anyway. If those grantees ever want an official copy, with updates and support, they come back…
The problem is with someone taking your whole software, branding and marketing it as their own and undercutting your service for half the price, not individual using it for personal reasons.
And it's not a service, it's a copy. Customers are explicitly allowed to resell it, and they have. And I still earn enough cash to continue developing it.
And I have the search engine top hits. And I have thousands of social media comments linking to my website. Copying a business isn't just about copying the product. They have to copy my reputation, too. And my sales channels.
Stop being so afraid. Selling free software is good, and sustainable, and those who think otherwise are extremely naive, ignorant, or with ulterior motives.