Straw Buyers

In reports on illegal guns and resultant gun violence, I hear the term "straw buyer" quite a bit. I know what it means, but I wonder why that term is used. Every time I hear someone say "straw buyer", it makes me think of the Scarecrow from The Wizard of Oz buying guns for the Cowardly Lion because the medal didn't work and he thinks carrying and wielding lots of big guns will give him courage. And of course the Cowardly Lion must use a straw buyer because he is forbidden to own guns due to his repeated assaults on civilians: assaults he makes to try to prove he's brave. I guess pretty soon he'll start drinking liquor to give him liquid courage and he'll start shooting up Oz, at which point he and the Scarecrow will get arrested and tossed in the Wizard's dungeon. (Or else the Wizard will just let the Wicked Witch do as she pleases with them both.)