if I read a lot of the rules threads, I would likely agree with you. However, I tend to look through various threads for new ideas, or fresh takes on old ideas, that I can pirate for my own campaign... and, since I'm the DM, that usually involves creating bad guys and using them in creative ways within interesting scenarios. And, also creating interesting locations and NPCs - the "flavor text" of a campaign.
I've been gaming for 30+ years now and I've been online since the early to mid 90s, or more than half of that time. So, I tend to know what I'm looking for most of the time when going through forums on the internets (anybody remember WebRPG from the 1990s? I found a fantastic gaming group and a great DM on there)