Why? Two reasons: Morons burn themselves up. You don’t see any “Blitz” branded cans anymore. Why? Blitz got sued out of existence due to the normal spouts on their cans. The lawyers said the spouts should have had expensive flame suppressors in them. The new safety spouts solve the “problem” in a cheaper way. Second reasons is morons who just leave the open spout on their cans and let the gasoline evaporate into the air rather than resealing the can. The evaporation is pollution. Air (oxygen) in the can promotes gum formation. And the morons wonder why their small engines are so hard to start or won’t start after the light ends of the gasoline have evaporated (needed to start engines) or the carburetor is gummed up after short term storage.