Headcanon that Harley is an Instagram freak because it’s a more socially-acceptable way to get out his obsession with taking pictures of people. And himself. He’ll post like 10-15 selfies a day, even take some when he is walking onto the stage for a contest appeal.
Of course he is a rude ass on Instagram too, but it’s why his (many) followers love him for it. He can get away with being mean because he does it in a humorous way. Like when May is onstage doing an appeal he snaps a pic and has ‘Aww, break a leg girl!! (..No seriously,..break a leg LOL) #ShrimpToast #No2ndRound4U’.
It also helps that May and Drew don’t have Instagram. Well, May wants one but she really only wants to take pictures of her food and of course Drew just flat out protests against getting one because he would never post anything because he doesn’t want the world to know what he’s up to. But then Harley gives him the most flack and uploads pictures of Drew to make him mad (almost all pictures are of Drew scowling since he can tell when Harley is doing this, and some pictures are blurry since Drew is physically batting the dumb device away). Harley’s hashtags for Drew are always #GreenHairDontCare and #WhatNotToWear