Think of their node like a relay. If someone is online, then the data might be p2p but Keet acts as a blind storage peer too. I don't think they worked it out but I think they wanted to figure out an incentive model so others will do this too for payment. Like a cloud storage sort of thing but fully encrypted and no accounts. If they figure that out then you get a pretty reliable solution without keet being the altruistic backbone. Not there yet afaik.
keet does relay but only for text currently, the reality is the relaying doesnt work very well and its better to have a peer in the room always online
Join me on Keet.io - The Psychedelic Libertarian Repository (no expiry) pear://keet/yry5f6hctja4dwbmpfxbpngqgjp6oiz3hqtzhimcseumfusi3koaeykkdtpe7u4pkubpkt4tykmjrpknr5an9ncjnw63w711x1q8pmkeqc