You seem to be stereotyping quite a bit. I was once a raider in WoW, now I only do content solo, and I love battle pets. Just because you've met a lot of elitists doesn't mean everyone who enjoys more challenging games are uptight assholes hating on everyone.
Is it really that strange that some gamers enjoy playing a game that gives a sense of achievement? Take rock climbing for example, at first you might like to climb whatever mountain or hill that you have access to, but later on you might want to try higher mountains, more dangerous places, and before you know it you're making plans to climb Mount Everest. But why would you do that? You could die! It's because pushing yourself is something people find fun, but probably in different areas of our lives. I rarely push myself in anything I do outdoors, so I do it in games.