This is a really nice thing to offer people, but with places like DigitalOcean offering one-click Mumble deployment for $5/mo[1], Guildbit might be a service looking for a niche.
Yep, this was the idea. The target audience are mostly gamers who want to get a quick server up and running, especially for PUGs (pick-up groups in MMOs). Most guilds already have some type of voip server they setup or are subscribed to.
I think they already have a nice, as they say on the page: if you want a one-off mumble server for a raid etc for free.
And it's still ~half the price if you want to go with their paid option (unless you destroy/recreate your d-o droplet between uses -- then those 5/month would go a long way).
[1] https://www.digitalocean.com/community/tutorials/how-to-use-...