[bballer]

It's what the author is doing with this post.

[protoduction]

I don't think that's fair, the author is not selling anything - they took the effort to put together a good resource for others to use and are sharing it for free.

[khuknows]

I don’t think I see what you mean here. Where am I selling a list of business models?

[hobofan]

I guess the interpreted the "opportunity" as "build a marketplace like these ones" instead of "those are marketplaces you can list your product on"?