Context: T3chFest is a non-profit technology event in Madrid organized by students and alumni. Tickets are free for people under 23, and the rest are 6€ that are donated to NGOs. Everything is paid by sponsorships and donations.
The event is happening in 4 days, so their logo and name is already printed in all the leaflets, graphics, merchandising... and of course it's been in the website for a long time.
The sponsorship quantity is probably less than 5K€, a small amount for Couchbase, but big for the volunteer organizers.
Sponsorship: https://t3chfest.es/2023/en/patrocinadores
Organizers: https://t3chfest.es/2023/en/organizacion/