I've done four competitions, and my coach was only there for my first one, which was at home rink. She had lots of skaters competing and no travel costs (she lived 2 minutes drive from the rink!), and she wouldn't have been able to coach anyway (I think there was a short morning patch, but she didn't want her skaters to do it the day of the comp anyway). I think I paid her £10 or £15??? (a lesson is £16 for half an hour). She did a warm up for us (skaters in the same group together), and then put us on the ice for the warm up and the competiton. In my case, she also had to do a mad dash for my spare CD and then for her ipod as I had music issues. Then a hug of relief at the end!
The other comp I did last year there was one other skater, who didn't have my coach. I'm sure my coach would've put the other skater on the ice as well if asked, but she was on holiday at the time anyway, so it was a moot point.
The two I've done this year I was the only one from my rink going, and as money is extremely tight, I couldn't have afforded for her to come with me anyway, and I think she knows this, so didn't suggest it.
I got adopted by other coaches at both comps though! At the second one, another coach actually offered to stay for my warm up and put me on the ice (her skater had been in the first warm up group, I was in the second). She was ill though, so I said she didn't need to. I don't think it would've been helpful except as moral support, as she doesn't know me or how I skate, so can't know what is fixable in a 4 minutes warm up and what just isn't! I don't think it's a chore for coaches, they enjoy seeing their skaters do well and beign there to support them.
I think when the kids go to other comps, they split the cost of the coach's accomodation and usually she'll get a lift up with one of them, or they'll share her petrol costs. This is where the coaches who have a million skaters win out, cause a) they can charge everyone a flat fee and make way more than if they'd actually been coaching, and b) the parents feel they've got a good deal cause the actual expenses are relatively low cause they're split between so many