Problem: Sometimes you write an article about a subject far away from where you live and there are no copyright free photos or videos available.
Proposed solution: We're a community with members all around the world. Someone must be near the object you're writing about: a piece of art, a building, a statue, etc. Ask those people to photograph it for you.
Who would benefit: Eventually, the whole of the wiki community, because there will be a stream of copyright free photos and videos available for all projects to use.
More comments: It's really just a place where the requester and the requestee can easily meet each other. For example, I as a Dutchman, residing in the Netherlands, want to write a Dutch article about some animal or a plant species in the Australian Outback; great if I can post a request and an Australian volunteer picks it up who doesn't mind to snap a photo of that animal or plant if he/she has the opportunity.