I've always encouraged small non-commercial hobby projects to use GitLab. It just seemed like the right thing to do.
If you're familiar with Paradox Interactive Studios games (Crusader Kings, Hearts of Iron, Stellaris):
- Star Trek: New Horizons (127,000 current subscribers)
- SW:Fallen Republic (97,000 current subscribers)
- Kaiserreich (774,000 current subscribers)
are (/were) all hosted on GitLab.
A lot of the people who contribute to these projects only do so intermittently (so high member count to work done ratio) and are usually doing this in their formative years so would be likely to continue to use GitLab when they enter the working world.
There is absolutely no money available as game publishers prohibit it. And even if they tried to sneak in some Patreon donations there's no way that's going to cover $19/m/user!
Honestly, GitLab really seems to be falling far behind in their outreach. Their Open source programme is behind GitHub's and they don't have anything for Non-profits.