The person who would find Date Movie funny has never seen Airplane. In order to appreciate Date Movie, you would have to completely forget the concept of a movie parody. There's certainly a lot to make fun of with romantic comedies like the sappy music, the loveable but hapless hero, etc. but Date Movie doesn't do any of that. Instead, it just makes a lot of references to other romantic comedies. They don't really make fun of them, except to put in some weak or gross twist on the original scene. This movie doesn't even make sense unless you saw the movies they were making fun of. There were parts where I thought to myself "Why is this happening? Oh, it must be a reference to a movie I haven't seen before."
My goal with this is to keep anyone else from ever seeing this movie. Date Movie needs to flop so badly that they not only never make a sequel, but it makes Hollywood re-evaluate making movie parodies to begin with. Because Date Movie shows that the studios have forgotten what movie parodies are.