This sums it up. End of thread.
Why Not wrote:
I think somebody else said it, intensity. A lot of people on here train hard, which means suffering. And running is all about suffering and pain tolerance. No timeouts in racing right? I think a lot of people object to ultra running because there is so little intense training involved. And so it's seen more like professional hiking, jogging. Just speaking personally, the dozens of ultra runners I know do not do repeats of any kind. Now they'll go hike/jog/walk/run for 8 hours on a Saturday or Sunday, but if I ask them if they want to do mile repeats they cringe.
I think some people get jealous of all the time ultra runners seem to have. I'd like to be able to spend a lot more time in nature than I do, but I can't, so I run in the concrete jungle and around in circles on a track. To add another generalization to the mix, ultra running is a sport inhabited by more single/divorced/people with grown up kids who don't have as many restrictions in their life.
Finally, I think some of its confidence. Most ultra runners I know just don't give a crap about times or what people think about them. Whereas some people on here, wink wink, care quite a bit about every second of that 5K pr. People who are OCD about running perhaps subconsciously wish they could let go, and just enjoy a run through the woods, or running through the woods.
So I think you could sum up a lot of the hate as disguised jealousy. Ultra running is running without the intense training, done by confident people who have more time on their hands than the average person. And that pisses off a lot of people who train really hard, run painful repeats, care intensely about their 5k time and wonder if it's all worth it.