Well, you were right all along about the canopies in UK. They are to keep us dry. Fire precautions here are limited to the scattering of manual fire extinguishers that you see around the petrol stations along with the buckets of sand.Well, you learn something every day. I feel a bit stupid, as it seems totally obvious now that I know it, but I did not know this is (presumably) the primary reason why petrol stations have canopies. I just kinda always thought it was so customers were kept dry and didn’t all go to the one station in town with a roof whenever it rained.
But the most important fire precaution is the regulation that you cannot lock the petrol delivery nozzle to "on". So you must stand and hold the trigger in when pumping fuel and it shuts off at once if you drop it. So very little fuel can escape by mistake.
In some parts of the USA, nozzles can be legally locked in the "on" position. So the risks are higher and, presumably, elaborate fire suppression systems are justified or mandated.