The exact original recording behind this clip is not clearly documented, so it is best understood as an internet joke rather than a line from a film or show. Its humour comes from pairing Batman, one of the most famous superheroes, with eBay, a familiar place for second-hand and bargain finds. Shared as a short soundboard clip, it fits the kind of quick, title-driven humour that travels well in memes, edits and reaction videos, where the joke is understood instantly without needing the full context.