I would think you would buy an iron sword over a bronze sword.
Poorly made iron swords are more likely to break.
And while iron will hold an edge better, swords don’t have to be all that sharp. You don’t have to be going very fast on a motorcycle for a round fence wire to be lethal.
They used what they had, and didn’t necessarily buy, they made them. Bronze remained in use for a long time. How long? It’s still in use. :^)
In the bronze age? Steel was not present.
Iron swords were horrible. Even with the advent of cruder steels, bronze took a long time to be replaced. It was sharper, less brittle, and could be harder than the available iron, and could be repaired much more easily.