Sounds like theft to me. I would sue in small claims on principal. But thanks for sharing, noted: I will never sell on Etsy lol
It doesn't matter if it's YouTube, Paypal, Amazon, or esty. Going alone is harder and more expensive.
The other options is to change regulations and that's something can't merely be done by a person.
Board Games has PAX. Anime conventions (ie: Cosplay accessories) have Anime Expo, Otakon, etc. etc. There's more conventions than I can keep up with these days. Almost every single one has an "Artist Ally" or other small shop where you can hawk unique goods to people.
It really depends on your niche. Maybe a state fair (farmers?) is where you set up shop. Etc. etc. I'd honestly try to setup at those places first these days to test out a product idea.
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I don't know anything about vanlife. But I dunno, Burning Man maybe? Where do vanlife people meet up?
Quartzite Arizona, every January