As an online game hacker myself, I feel I can answer this.
Why do I exist? Well, because many moons ago a couple people made some bad decisions, and for some reason decided to follow through with them.
But I assume you're actually asking why I hack online games. In short, there are two reasons. First, to see if I can. Some gamers play for achievements, others for competition, and me, to see if I can break things. I get a great sense of accomplishment from doing something that not only was I not meant to, but I was able to get by the system in place to stop me. It's like achievements on steroids. The second reason, is that often by doing so, I get to see content not meant to be public. I get to play with the Developer's Sword of 1000 Deaths or whatever else I can find buried in the code that is not typically obtainable. Sometimes, I do it to prove a point. "Skeletron drops Red's Wings!!!1!" No, I can confirm it does not. How? A bit of hacking.
The most important question you asked is why can't we give gamers a fair go.
Personally, I do. I only use my abilities for exploration, or at worst, to prove a point beyond the ... point... of deniability. I can point something out to a developer. As a bug report, it would sit on the shelf for years. But when they see me doing [whatever it is i shouldn't], my trash account gets banned and they *fix the bug immediately* (at least, in many cases. I'm looking at you, Runes of Magic. You're welcome.)
Humans need instant gratification. Unfortunately, making a point to a couple people is often not enough. Some take their enjoyment out of godlike powers in PvP. Personally, I'll occasionally abuse glitching in PvP, but my rule is nothing that requires external tools or hacking knowledge. So at least its "fair cheating", as every single player present has the capability to do the same, if they'd train their Google-fu beforehand.
It is tragic that not everyone has a code of ethics, and I'll apologize on behalf of "my people". Give someone a shiny red button and tell them not to push it for all eternity. It's 100% guaranteeable the button will be pushed before the end. Some of them just get a little too crazy with it and spam the crap out of that shiny red button. Not sure what to say about them - they suck to their fellow hackers just as well as the rest of you.
Also, wrong forum.
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