Yes, that was my thinking too! Not so sure about the trailer, it would have to be quite hefty to get a generator in there as well....or a very long length of cable! But really I didn't buy it specifically for one bike so the electric start wasn't really an option, not to mention the whole thing came to less than £300 all in....
Realised it has another benefit today as well, I've just finished some engine work on another bike and tried it on the starter for 5 or 10 minutes without plugs in just to see oil was circulating etc....got up to over 30mph on the speedo!