Thanks greywolf. Yeah, that just didn't seem right to me. If the main is 30A, that means that if something went awry 29.9A could be going through those skinny little wires. What's even more surprising is the headlight wiring, and lack of protection there: the hot wire runs from the starter relay, up to the ignition swith, then to the hi/low switch, then back under the seat to the fusebox, then (finally) to the bulb. A short in that wiring "upstream" of the fuse would blow the main, and maybe fry a few wires before doing so.
I'm no electrical engineer (but I did stay at a Holiday Inn Express last week), but it seems to me that the fuses should be as close as possible to the battery to protect as much of the wiring as possible. Is there something I'm missing?