Nice piece, thanks for sharing π.
I've taken part in a number of mountain trail running events in New Zealand - no ultras but a few half marathons - and you're right, it's the community that makes it all the more special.
Much like yourself, I always take a minute to thank the aid station volunteers and event organizers, as well give encouragement to any runners who pass me or who are struggling.
I've always thought about doing an ultra and maybe one day I will. Though it will take some training to get to that level.
Thanks again for sharing your experiences and good luck on your next race π.