Anything that isn't fun and isn't good doesn't even enter most people's minds, because there's no reason to do it.

Unless you have a really broad definition of 'fun' you're quire wrong here. Sometime people will experiment. Sometimes people will do what they're told not to as a gesture of defiance. Sometimes people will do things that are very harmful to themselves because it is the only way they can strike against forces they are otherwise powerless to resist, like an abusive partner or guardian. Sometimes people mistakenly think they don't have any other options, sometimes those people aren't mistaken.

If you want to talk about the First World, then maybe you're just barely right with your 'most'; I doubt it, but I think we can just dismiss that possible interpretation instead. Because outside the First World you're quite mistaken: many things that are not fun or good enter into the majority of people's minds.

An amoral man doing stuff he finds to be good fun will generally cross the line to evil precisely where he starts doing all the stuff that he enjoys and that isn't common, because if it's enjoyable and morally acceptable, it'll be common already.

Plenty of evil things are quite common. I had a list, but I don't think it actually adds anything to the comment when I all need to say is "emotionally abusive relationship." They're common enough that it's been claimed they're in the majority.

Well, some people confuse Teh Evulz with awesome.

I don't think they're confused at all.

I am some people, and if evil ain't awesome then I'm confused.

It's generally high-risk. A lot of the obvious examples have overvalued rewards. Much of First World society protects people from it. And that's good, because I like having some protection from people who are better at evil things than I am at defending against them.

But there remain opportunities. And there remains awesome.