Anonymity, superior and or inferior complexes, or what they perceive to be entertaining to impress friends. Those are generally reasons. Otherwise, there are other motives.

Personally, I suck at fighting games. Never been any good with remembering all the combos. It's more or less just human nature that you're seeing. It's not just an internet thing. People do worse stuff in real life everywhere. Why would they be nicer on the net?

Yea my bad. Ironically talking about raging little gamers gets me worked up :p

It's been a really long time since I sat down with Tekken Tag 2.  I have not been in practice mode since starting back with it over a month ago.  I'm still going soley on what I hadn't forgotten.  It's not about remember the combos.  They don't mean anything if you can't hit the guy anway, but I get what you mean.

It's called the Greater Internet Fuckwad Theory

http://knowyourmeme.com/memes/greater-internet-fuckwad-theory

Its definitely not the high road, but I love to be a sarcastic jerk in a passive aggressive way to people who are being assholes.

For example in League of Legends, if someone is being a dick I'll post their score in global chat every time I kill them/they die. Its small, but almost always pisses them off.

Might I add, that you should be happy that you feel like the majority of the human race are gobshites. I mean, that leaves the rest of us as calmer superior beings who can express ourselves logically. 

It's a faceless, often anonymous platform, with little to no actual "real world" consequences (IE people can't punch you in the face), so many people feel "phony tough", or as it is often called "Internet Tough", and feel like being assholes to people. Sometimes they're just trolling, thinking that it's funny to be mean. Other times? They're just being mean. Me? I still try (often in vein) to get ACTUAL conversation out of folks on the internet.

Imagine that, eh?

The best thing you can do, if you genuinely enjoy the game and are truly annoyed with those idiots, is to find your character and practice. Eventually, within a week or so, you'll be a force online. Copy down their usernames then invite them for a game when you're better. Then politely remind them who you are, and what they said about you after you beat them. Or if you don't want to do that, then stoop to their level and hurl insults back. Tell them you're too busy with life to learn juggling combos and that the only boobs they'll ever see are in 1080p running at 60fps.

Then record a fart in a voice message and send it to them.

There's either loud and obnoxious manboys or holier-than-thou hipsters who know more than you. It's a huge turn off.

That being said, don't let a few hardcore masturbators ruin your experience or put you down. Everything has it's fair share of wasters, from music to television shows, sports to video games.

They didn't eat their vegetables growing up, or people are just assholes when they don't have to take responsibility for what they are saying