I don't think that this is the most pure running format. I don't know what that would be, never having aimed at purity in running--maybe it's kids playing tag.
Financially, though, this doesn't sound that bad. One must go through quite a few pairs of shoes every year, and there's the cost of travel to such competitions. Plenty of people like to ski, and I can imagine they drop a lot more money on that.
Skiing is mentally and physically genuinely enjoyable. Endurance/exhaustion running is defined as at least 12-hours of pain, which to me translates as "proselytization via self-flagellation". I hope the sense of achievement they get at the end is genuinely worth it.
Financially, though, this doesn't sound that bad. One must go through quite a few pairs of shoes every year, and there's the cost of travel to such competitions. Plenty of people like to ski, and I can imagine they drop a lot more money on that.