because of the reasons I've mentioned already in 1st comment.
(perhaps later I'll make my own detailed post on this subject.
thanks for giving me an idea ! 🙂 )
BTW the phrase "conspiracy theory" is an oxymoron in itself.
also, apart from being used as "ad hominem", it is also sort of "straw-man" and may be in some sense "red-herring" too. 😃
(well, that's interesting that it is related to so many )

what other name would you use?

can use many various names, say: entertainment, fun (or boredom), trolling, promoting / generating traffic / click-baits / eye-catching headlines/ sensitization etc etc - just on such a short notice, list can go on and on...
Yellow press employs many of these different tricks for what, already couple of centuries?
while ordinary users of internet (and social media) are most likely just trying to get more followers / subscribers / likes (votes) etc - which all comes to trying to Earn more.
I doubt it very much that majority of those people who publish all that stuff believe it themselves. LOL

although won't be surprised if there are all sorts of agencies which purposely spread such various info "info-injections" into crowds - for all sort of purposes; most basic one: to divert public attention elsewhere when needed... kinda "Kansas city shuffle" ... like for example now this ongoing "show must go on" all over internet and YT about girl from Dr.Phil's show and that it's apparently a "fake story" (good point about deception mentioned in there)