There's no way one could ever make a living on selling stuff in OpenSim like some manage to make a living on selling stuff in Second Life.
First, in SL, you have to pay for just about everything anyway. Making it on only freebies is so difficult it's a challenge. In OpenSim, you can do just about everything without ever paying a penny.
Second, OpenSim has a whole lot fewer users than SL. Even if everyone had money, and everything cost money, you wouldn't make nearly as much.
Third, of these users, only a tiny fraction has in-world money to begin with. They're probably fewer than those who are fully convinced that "Never buy in OpenSim" is an official OpenSim slogan.
Fourth, you'd have to compete with professionally-produced, almost-industrial-grade, premium luxury content stolen from SL.
And fifth, even if you can pull that off quality-wise, someone will god-mode or out-right copybot your stuff and put it into their own freebie store free and no-transfer, renamed and declared their own original creation. And then someone else will god-mode that and offer it free and full-perm.
That said, sometimes god-mode is a blessing, especially for freebies whose creators are no longer around.
For example, something is wrong with a freebie, e.g. it's glow-in-the-dark full-bright because whoever made it had always set their viewer permanently to midday. But that someone hasn't logged in in forever or doesn't respond otherwise or takes any bug report as an ad-hominem attack. And that item is no-modify. Then you can throw it away and try to find an adequate replacement. Or you can god-mode it, turn full-bright off and have something actually useful.
Or you want or have to move to another grid. Of course, you want to take your stuff with you. But some of it is no-transfer, it's very dear to you, and it isn't available anymore anywhere because the only shop that offered it has disappeared. You can either leave it behind and carry on without ever being able to use it again. Or you can god-mode it, make it full-perm for personal use and share it with your new avatar.
Or something is actually supposed to be full-perm, maybe even as per the license notecard inside the item or the sales box. But there's only one shop left offering it. And the owner of that shop decided to make all items in that shop no-transfer so that nobody could build a competing freebie sim from items from this shop. So this item is only available no-transfer although it should be full-perm. Again, you have the choice: Either leave it as it is and watch it vanish when that shop disappears. Or god-mode it back to full-perm and share it.
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