I've filled my ST1100s for many years while sitting on them due to various physical afflictions in my lower extremities. But then I've been know to run with scissors also ...
One trip to Canada it was so painful to mount and dismount (I was carrying a walking stick), that I would get on in the morning and not get off until I reached the destination. Understand that
1. The ST1100s are efficiently watercooled and don't really run that hot unless you get caught in traffic.
2. The ST1100 bodywork tends to shield the engine very well from errant fluids.
3. The ST1100 gas opening has a nice 'catch bowl' around it with a drain pipe to ground.
I have doused the bike with gas while not on it when I looked away and the automatic shutoff didn't work. No ST1100s were harmed in the process, but it sure stunk for a while. And when I do get off, I do put the ST1100 on the centerstand because if you decide to get into one of the saddlebags, you could tip her over if you are not thinking well. ;-)