If you place the container on the ground, and keep the nozzle in contact with the container, you will not generate a static spark. When filling flamable liquids in industry, the containers must be bonded to each other (a cable connects each of them together), and the whole collection of containers is grounded. All to stop static sparks.
If, however, you take your plastic gas can and place it on the plastic bed liner of your pickup truck, and pour the gasoline into the container without being in contact with it, you will develop a big difference in charges between the ground/truck/nozzle/can. Your chances of getting a spark are quite good when you connect two of them together. Anytime you take a flamable liquid as potent as gasoline, confine it in a can, and subject it to a spark, you’re going to get a boom.
And no, this isn’t like the cell phone scare. There have been at least a half-dozen fires caused by improper filling of gas cans in plastic bed liners.
Keep those cans on the ground, people.
If your red lights are melting, you’ve parked too close.