I don't think it is a pain to them at all, they can tout their races at high prices as people will pay them, now tri has lost momentum ultras are gaining more interest from people wanting a challenge. Unfortunately there is a whole new group of people moving into it with higher disposable income who are not as bothered by the price as they can afford it. It is a shame but probably the way it is going to go until ultra becomes yesterdays big thing just as is starting to happen to tri!!
At the end of the day they 'can' be run on a shoestring, some organisers 'justify' their costs and then make big profits, sometimes that goes to charity sometimes not.
To me the challenge of ultras is to do as much myself as possible, so having the minimum of support etc makes it more of a challenge. There are many people who finish 50 mile or longer ultras under well supported conditions who would not be able to go out and just do that off their own back with no support, to me they have not actually done the ultra, I don't see ultras as a team sport but I accept I am in the minority!
I don't have a problem with that after all it is all about the 'personal' challenge