As long as we eat, there are going to be assholes. But while a physical asshole deals with vital processes, the Internet asshole does the exact opposite, pouring out unnecessary shit in front of everyone.
Shouting "FIRST" is a spiritual sphincter failure.
Most online idiots are extensions of stupidities we have in the real world: con artists, zealots, homophobes, and others who project more shitty internal problems than an IMAX colonoscopy. But some people evolved to exploit new niches of assholery in the online environment, like those worms that live in the human colon. Except we'd rather have the worms, because there are pills we can take to kill those.
"Take this, MingeKampf420!"
Behold, the goatses of the five biggest social media services.
Twitter: The Disapproving Follower
Twitter is an online intelligence test. You choose who to follow, so how happy Twitter makes you is a direct indication of your own abilities. You can get insights from some of the coolest people on (and off) the planet, or an endless stream of Instagrammed sandwiches and illiterate swearing. It's the Internet equivalent of that evil tree-cave in The Empire Strikes Back: You could go wading hip deep in filth and end up fighting lunatics, but that's only a reflection of yourself.
The most metaphysical dick-waving contest of all time.
If you don't like someone, unfollow. Done. But the disapproving follower instead starts a single-handed siege, determined to change the mind of someone they've never met with nothing but retweets and OTHER ALL CAPS STATEMENTS, USUALLY SWEARING, YOU FUCK. Instead of moving on with their lives, or discussing differing opinions, these morons clutch harder to the burning coals of their own hatred as they scream, "STOP BEING SO HOT, YOU FAG!" (Note: That's also the secret thought of many homophobes.) They usually claim to be defending deep beliefs. Deep beliefs so insecure that anyone else in the entire world disagreeing reduces them to frothing rage.
If you're using a global supercomputer network to find the one person whose short messages disagree with you, you'd damn well better be Batman chasing the Riddler.
Facebook: Horror for a Cause
Each service has a function. Twitter turns everyone into fortune-cookie generators, and Facebook is the restaurant they're hanging out in. Despite becoming Exploit Your Personal Data for Profit Incorporated, hundreds of millions of people still use Facebook, because it's the easiest way to stay vaguely aware of friends and family without actually talking to them. You see big announcements, birthday parties, when people are back in the country, and bloody pictures of festering animals and dead people.
Surprise! One of your friends is an asshole!
This is someone who cares so much about a cause that they electronically trigger gore porn. And anyone using the same plan as the Saw movie villain is clearly in the right. There's no doubt that some of these causes are important. But you were grinning at your nephew's cute Halloween party and chatting with some friends about going to the pub. If someone heaved a mutilated corpse into either of those situations, you'd hate them then, too, and subconsciously you now hate the goddamn disasters for interrupting your comfy life. Which is terrible, and selfish, and precisely the complacent attitude the person was trying to get you out of, but they've just made it worse. When someone is taken by surprise and given the choice between "look at pus-filled horror" or "fuck off," it's option 2 all the way.
"This Internet is full of naked bodies, and you want me to look at dying dolphins? Talk to the hand. But be quick. I'll be using it in a minute."
You want us to donate to worthy causes? You're right, we should! In fact, I do, and for each cause it was because someone cared enough to make a real point. If you want to convince your friends and family, write them personal messages. If you want to convince followers, write a post. Both of them require actual effort. And are therefore infinitely more effective than taking a second to feel righteous about clicking "share" on horrorporn. Worst of all, this doesn't have the same easy fix as Twitter. You could just block them from your friends list, but unlike them, you're not prepared to sacrifice chunks of your social life for a cheap emotional reaction.