Warning: stupid question ahead.
What are these paid options for??
They are like an hosting/support plan, right?
The real question is, as i've installed nodebb in my server, i'm not breaking any license, am i?
It's GPL, isn't it?
The software is open source, you're free to host it yourself. The pricing options are for users who want a forum, but don't want to deal with hosting it themselves.
There are other perks, @julian's personal phone number for 24/7 support and Baris will send a signed photo.* So it's worth it really.
*I don't believe you get either of those, but it's worth it anyway.