Too many stations in my area of the US (western Ohio) allow this. I was a cashier at my family's independent gas station for a number of years, and it always pissed off customers when we stopped the dispenser when they walked away / got in their car / etc. It's a legitimate safety and environmental hazard (some hold-open latches don't disengage reliably on some filler necks leading to gasoline rolling out of the tank onto the ground). People get used to lax non-safety conscious stations and then act like jerks to the employees in stations who do care.