There're always a big group of meme fans. Humans love their funny photos.
Aliens want to run when Big Chungus come and Hit Or Miss is the second favourite song in the room "of course first is Rick Astley's Never Gonna Give You Up." -- Anon Guest
Memetic communication is dependent entirely on the familiarity of the recipient with the subject. Some, simple images with even simpler captions, are easier to communicate than, say, a mish-mash of images with contextual dependency that requires familiarity with their embedded memes.
Archivaas will be happy to inform that the peak of 'meme-ception' occurred in the noveau-post-post-dadaist period of the early Twenty-first century, shortly before the Green Revolution, and decades before the Shattering. The surviving images from that period require explanations of well over a thousand words, thus destroying a well-known Terran saying.
Not all Humans are familiar with all known memes, especially since memetic mutation is dependent on large, interconnected communities. Some in isolation have lost some memetic formats and, though re-education is quick, no joke is ever funny after it's been explained. However, some memes are universal, Bohemian Rhapsody, aka "The Human Anthem", is one such example. Rickrolling is another, as is Loss. In fact, it is quite difficult to predict the founding structure and subsequent memetic replication once shipboard culture starts to grow.