This never really bothered me. I wouldn't mind having a flip-up cap that stayed with the bike if it's designed well, but I'm really not afraid of scratching my gas cap. I mean, the bike is only $~6500 new. And it's going to get scratched, and minor scratches really shouldn't hurt it any.
I always get off of my bike, take my gloves and helmet off, and typically set those down on the triple tree (helmet resting on the gloves). Sometimes I might hang the helmet on my right handlebar, or set it on the curb next to the gas pump, arbitrarily or if it's windy. I leave the key in the gas cap, and I set it down typically on the concrete "curb" surrounding the pumps (next to where I'd put my helmet), "face-down" resting on the key and the edge. I reinstall the gas cap and if I didn't pay at the pump put the key in my pocket immediately after pumping. It's really no different than you'd do with a cage (except with the car I typically rest the cap on the car itself because, again, **** scratches). I don't even really want a vehicle that I have to baby that much. Why would you? I'd much rather be able to afford the vehicle and scratches be damned. Those are love marks. That's life. Sorry, the vehicle has been used. Tough.
Around here, most gas stations refuse to fill up bikes. I don't know if they're afraid their employees will drip gas on the bikes and people will get mad, or if they'll be nervous/clumsy around bikes and scratch or drop them or whatever, but yeah. At full-service stations I've had them say, "We're not allowed to fill it for you," and hand me the pump. I was a little bit uncomfortable with letting them fill my bike anyway so I didn't really mind, but I doubt I'd care unless they did something stupid like drop the bike or sit on it or something.. :angryfire
I think there was one gas station where they did pump my gas for me, and again I didn't really care either way. In the cage it's nice because you don't have to get out. On the bike, I don't really care because I have to get off anyway. Unless I want some dude handling nozzles in my groin area... :eek Not that there's anything wrong with that if you're into that sort of thing...