I couldn't find this answer either. It's difficult to trust someone with large hosting / development / etc costs but no business model. It's not a charity. How do they "keep the lights on" with no fees?

Why would they have large hosting costs? They don't do anything except have a website where you can download the OpenBazaar software individual stores are self hosted.

$1M in seed funding isn't that much.

At the moment, they're receiving donations [1], but it's entirely conceivable they're going for a similar business model to MySQL's original authors: selling support, consulting services, and training for their products.

[1] https://blockchain.info/address/3MXYUBLWNETa5HTewZp1xMTt7AW9...

The network effects of this will be pretty strong if this takes off. If they have a large captive audience of people with their wallets open, ads could be pretty effective/lucrative (and there's no adblocker if they own the browser).

They are probably hoping the marketplace takes off then they will offer hosted stores to merchants who don't want to deal with setting up their own OpenBazaar node.

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