The use case for the meme database is slightly different: it's to find that meme you saw somewhere else. Local search isn't enough then.
Though I share your feelings somewhat - I was completely surprised by what you wrote in the comment higher up about iPhone gallery search. I didn't realize this is possible in a reliable fashion, much less off-line and deployed in a mass market device.
Complete supposition: maybe teens' exposition to memes is through non-private messengers and apps, meaning all media is saved automatically on the phone and available through a search. I don't think the web is very much used still.
Yes, and the database is useful for all the situations when you saw a meme on someone else's device, or embedded in some piece of content, so you had no way to save it.
Though I share your feelings somewhat - I was completely surprised by what you wrote in the comment higher up about iPhone gallery search. I didn't realize this is possible in a reliable fashion, much less off-line and deployed in a mass market device.