PSA: The only valid use of a hashtag is if _you_ care enough to click through and read the tagged tweets. Or as a joke. Everything else is 
I kind of round that use case down to "joking," but your point is well taken. #cecinestpasunhashtag
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Maybe I just want to let people know my post has a theme.
#hashtag -
Not allowed!
#nohashtagsforoldmen
End of conversation
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