You mean the heroes themselves, or the reporters?
I'll answer both.
Reporters: Ginger is only assuming they're the heroes backup, it's not that she ISN'T using her head, it's the problem she's overthinking. The only thing she got right in the scenario is Cheshire IS the field leader. In the comics, Magneto was back and forth between hero and villain, so the Captain's not sure if she can fully trust the girl with the magnetic powers. The speedster, as the farmgirl pointed out, is too young to be the field leader, at 16.
Heroes: The Captain, as well as other clean police, see these super powered people exactly as Rainier stated to Windy (which is why I loved that was mentioned by
@MsBloom in Rainier's lecture). "Deputized to help the police", with rules, will keep the heroes in check and keep them from going vigilante and causing unnecessary damage to property and people when nabbing the villains. IE Collateral damage, which the press would have a field day with, no doubt.
Hope that helps, and now we need to name this team of four so far.