The feather-fall potions were protection against a case that wasn’t supposed to happen. Harry doesn’t take precautions so that he’s licensed to need them, he takes precautions so that people don’t get hurt. Hermione falling wasn’t supposed to happen—he endangered her for the sake of a game. He raised the stakes farther than they were supposed to go, and it was someone else who could have gotten hurt.
The feather-fall potions were protection against a case that wasn’t supposed to happen. Harry doesn’t take precautions so that he’s licensed to need them, he takes precautions so that people don’t get hurt. Hermione falling wasn’t supposed to happen—he endangered her for the sake of a game. He raised the stakes farther than they were supposed to go, and it was someone else who could have gotten hurt.