Most modern vehicles have roll-over valves in the fuel neck to prevent fuel from running out in the event the vehicle tips or rolls over. It's going to block any sizeable hose from going down the neck into the tank.
What's wrong with multiple gas cans?
Aside from the newer designs being a PITA to use, they're pretty well sealed. One can or twenty, there's not much difference, especially if you're parking a car in there.
I have quite a few cans. They only get filled when there's an impending emergency. Once the power outage is over, I gradually consume them by filling the cars, boats, lawn tractor etc. They could be empty again the next day if necessary. For Irene, I have 15 gallons left over and will simply pour that into the vehicles when they're low enough to accept it.
We won't go there as to why the wife is dictating usage of the garage...