Well, the assemblies were usually about an hour's drive from home for us. The conventions did require a 100+ mile drive (travel time varied from 2-5 hours depending on traffic), and at least $400-$500 extra expenses to pay for the room and food and gas for the trips to and from the convention site.
It wasn't until I had a family of my own that I fully understood how hard it is to deal with that kind of cost. I can only imagine how difficult it is for people who earn even less than I do, and I don't earn that much. Guess you could use part of your tax refund, if you're lucky in that way (*ahem* fortunate).
But clearly this is a hardship on a lot of people. I wish I could offer further on that, but my knowledge is limited.
--sd-7