Supply and demand?
I don't know the details, but I do know my sister always carried two for her eldest (past tense because he's now in college and presumably carrying them himself now).
Medic units, that have trained personnel, that have all the equipment to draw up Epi from a $3 vial themselves, who are already on scene.
This leads to my county alone having to throw away $130,000/yr of EpiPens that don't get used before they expire. Because the state legislates that we're required to carry them.