I think this is because many citations are from people skimming through citation lists (e.g. gscholar) and trying to find one that sounds "right" to put in a "citation needed" slot. Joke titles are not transparent enough

also the first half of colon-ated science titles are very rarely unique, which makes that half of the title useless for indexing for example, approximately 835,000 papers use the phrase "less is more" in their title, many with the format "Less is more: xx science thing"