So, record-setting is pretty much out of the question. Most anyone who does go beyond the marathon extols the virtues of the pursuit. One by-product of running long is that you can actually get somewhere. Many of the USA's 17 100-mile trail runs are staged in some of the most scenic vistas in the country. There is also a unique camaraderie among runners.
Ultra races are usually small affairs.
The biggest race in the USA last year was the JFK in Maryland, with 719 finishers. Most are more likely to have 40 or 50 runners. As such, many runners either know each other, or get to know one another during the event. The less frenetic pace of an ultra affords time to socialize. In that way, these races are a lot like marathons were a few decades ago, when those who participated were part of a small fraternity.